Web Services Reliable Messaging (WS-ReliableMessaging)

Committee Draft 04, August 11, 2006

Document identifier:

wsrm-1.1-spec-cd-04

Location:

http://docs.oasis-open.org/ws-rx/wsrm/200608/wsrm-1.1-spec-cd-04.pdf

Editors:
Doug Davis, IBM <dug@us.ibm.com>
Anish Karmarkar, Oracle <Anish.Karmarkar@oracle.com>
Gilbert Pilz, BEA <gpilz@bea.com>
Steve Winkler, SAP<steve.winkler@sap.com>
Ümit Yalçinalp, SAP<umit.yalcinalp@sap.com>

Contributors:

See the Acknowledgments (Appendix E).

Abstract:

This specification (WS-ReliableMessaging) describes a protocol that allows messages to be transferred reliably between nodes implementing this protocol in the presence of software component, system, or network failures. The protocol is described in this specification in a transport-independent manner allowing it to be implemented using different network technologies. To support interoperable Web services, a SOAP binding is defined within this specification.

The protocol defined in this specification depends upon other Web services specifications for the identification of service endpoint addresses and policies. How these are identified and retrieved are detailed within those specifications and are out of scope for this document.

By using the XML [XML], SOAP [SOAP 1.1], [SOAP 1.2] and WSDL [WSDL 1.1] extensibility model, SOAP-based and WSDL-based specifications are designed to be composed with each other to define a rich Web services environment. As such, WS-ReliableMessaging by itself does not define all the features required for a complete messaging solution. WS-ReliableMessaging is a building block that is used in conjunction with other specifications and application-specific protocols to accommodate a wide variety of requirements and scenarios related to the operation of distributed Web services.

Status:

This document was last revised or approved by the WS-RX on the above date. The level of approval is also listed above. Check the current location noted above for possible later revisions of this document. This document is updated periodically on no particular schedule. Technical Committee members should send comments on this specification to the Technical Committee's email list. Others should send comments to the Technical Committee by using the "Send A Comment" button on the Technical Committee's web page at http://www.oasis-open.org/committees/ws-rx. For information on whether any patents have been disclosed that may be essential to implementing this specification, and any offers of patent licensing terms, please refer to the Intellectual Property Rights section of the Technical Committee web page (http://www.oasis-open.org/committees/ws-rx/ipr.php). The non-normative errata page for this specification is located at http://www.oasis-open.org/committees/ws-rx.

Table of Contents

1 Introduction

1.1 Notational Conventions

1.2 Namespace

1.3 Compliance

2 Reliable Messaging Model

2.1 Glossary

2.2 Protocol Preconditions

2.3 Protocol Invariants

2.4 Example Message Exchange

3 RM Protocol Elements

3.1 Considerations on the Use of Extensibility Points

3.2 Considerations on the Use of "Piggy-Backing"

3.3 Composition with WS-Addressing

3.4 Sequence Creation

3.5 Closing A Sequence

3.6 Sequence Termination

3.7 Sequences

3.8 Request Acknowledgement

3.9 Sequence Acknowledgement

3.10 MakeConnection

3.11 MessagePending

4 Faults

4.1 SequenceFault Element

4.2 Sequence Terminated

4.3 Unknown Sequence

4.4 Invalid Acknowledgement

4.5 Message Number Rollover

4.6 Create Sequence Refused

4.7 Sequence Closed

4.8 WSRM Required

4.9 Unsupported Selection

5 Security Threats and Countermeasures

5.1 Threats and Countermeasures

5.1.1 Integrity Threats

5.1.1.1 Countermeasures

5.1.2 Resource Consumption Threats

5.1.2.1 Countermeasures

5.1.3 Sequence Spoofing Threats

5.1.3.1 Sequence Hijacking

5.1.3.2 Countermeasures

5.2 Security Solutions and Technologies

5.2.1 Transport Layer Security

5.2.1.1 Model

5.2.1.2 Countermeasure Implementation

5.2.2 SOAP Message Security

5.2.2.1 Model

5.2.2.2 Countermeasure Implementation

6 Securing Sequences

6.1 Securing Sequences Using WS-Security

6.2 Securing Sequences Using SSL/TLS

7 References

7.1 Normative

7.2 Non-Normative

Appendix A. Schema

Appendix B. WSDL

Appendix C. Message Examples

Appendix C.1 Create Sequence

Appendix C.2 Initial Transmission

Appendix C.3 First Acknowledgement

Appendix C.4 Retransmission

Appendix C.5 Termination

Appendix C.6 MakeConnection

Appendix D. State Tables

Appendix E. Acknowledgments

Appendix F. Revision History

Appendix G. Notices

1 Introduction

It is often a requirement for two Web services that wish to communicate to do so reliably in the presence of software component, system, or network failures. The primary goal of this specification is to create a modular mechanism for reliable transfer of messages. It defines a messaging protocol to identify, track, and manage the reliable transfer of messages between a source and a destination. It also defines a SOAP binding that is required for interoperability. Additional bindings can be defined.

This mechanism is extensible allowing additional functionality, such as security, to be tightly integrated. This specification integrates with and complements the WS-Security [WS-Security], WS-Policy [WS-Policy], and other Web services specifications. Combined, these allow for a broad range of reliable, secure messaging options.

1.1 Notational Conventions

The keywords "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119 [KEYWORDS].

This specification uses the following syntax to define normative outlines for messages:

Elements and Attributes defined by this specification are referred to in the text of this document using XPath 1.0 [XPATH 1.0] expressions. Extensibility points are referred to using an extended version of this syntax:

1.2 Namespace

The XML namespace [XML-ns] URI that MUST be used by implementations of this specification is:

http://docs.oasis-open.org/ws-rx/wsrm/200608

Dereferencing the above URI will produce the Resource Directory Description Language [RDDL 2.0] document that describes this namespace.

Table 1 lists the XML namespaces that are used in this specification. The choice of any namespace prefix is arbitrary and not semantically significant.

Table 1

Prefix

Namespace

S

(Either SOAP 1.1 or 1.2)

S11

http://schemas.xmlsoap.org/soap/envelope/

S12

http://www.w3.org/2003/05/soap-envelope

wsrm

http://docs.oasis-open.org/ws-rx/wsrm/200608

wsa

http://www.w3.org/2005/08/addressing

wsaw

http://www.w3.org/2006/05/addressing/wsdl

wsse

http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd

xs

http://www.w3.org/2001/XMLSchema

The normative schema for WS-ReliableMessaging can be found linked from the namespace document that is located at the namespace URI specified above.

All sections explicitly noted as examples are informational and are not to be considered normative.

1.3 Compliance

An implementation is not compliant with this specification if it fails to satisfy one or more of the MUST or REQUIRED level requirements defined herein. A SOAP Node MUST NOT use the XML namespace identifier for this specification (listed in Section 1.2) within SOAP Envelopes unless it is compliant with this specification.

Normative text within this specification takes precedence over normative outlines, which in turn take precedence over the XML Schema [XML Schema Part 1, Part 2] descriptions.

2 Reliable Messaging Model

Many errors can interrupt a conversation. Messages can be lost, duplicated or reordered. Further the host systems can experience failures and lose volatile state.

The WS-ReliableMessaging specification defines an interoperable protocol that enables a Reliable Messaging (RM) Source to accurately determine the disposition of each message it Transmits as perceived by the RM Destination, so as to allow it to resolve any in-doubt status regarding receipt of the message Transmitted. The protocol also enables an RM Destination to efficiently determine which of those messages it Receives have been previously Received, enabling it to filter out duplicate message transmissions caused by the retransmission, by the RM Source, of unacknowledged message. It also enables an RM Destination to Deliver the messages it Receives to the Application Destination in the order in which they were sent by an Application Source, in the event that they are Received out of order. Note that this specification places no restriction on the scope of the RM Source or RM Destination entities. For example, either can span multiple WSDL Ports or Endpoints.

The protocol enables the implementation of a broad range of reliability features which include ordered Delivery, duplicate elimination, and guaranteed receipt. The protocol can also be implemented with a range of robustness characteristics ranging from in-memory persistence that is scoped to a single process lifetime, to replicated durable storage that is recoverable in all but the most extreme circumstances. It is expected that the Endpoints will implement as many or as few of these reliability characteristics as necessary for the correct operation of the application using the protocol. Regardless of which of the reliability features is enabled, the wire protocol does not change.

Figure 1 below illustrates the entities and events in a simple reliable exchange of messages. First, the Application Source Sends a message for reliable transfer. The Reliable Messaging Source accepts the message and Transmits it one or more times. After accepting the message, the RM Destination Acknowledges it. Finally, the RM Destination Delivers the message to the Application Destination. The exact roles the entities play and the complete meaning of the events will be defined throughout this specification.


Figure 1: Reliable Messaging Model

2.1 Glossary

The following definitions are used throughout this specification:

Accept: The act of qualifying a message by the RM Destination such that it becomes eligible for Delivery and acknowledgement.

Acknowledgement: The communication from the RM Destination to the RM Source indicating the successful receipt of a message.

Acknowledgement Message: A message containing a SequenceAcknowledgement header block. Acknowledgement Messages may or may not contain a SOAP body.

Acknowledgement Request: A message containing a AckRequested header. Acknowledgement Requests may or may not contain a SOAP body.

Application Destination: The Endpoint to which a message is Delivered.

Application Source: The Endpoint that Sends a message.

Deliver: The act of transferring a message from the RM Destination to the Application Destination.

Endpoint: As defined in the WS-Addressing specification [WS-Addressing]; a Web service Endpoint is a (referenceable) entity, processor, or resource to which Web service messages can be addressed. Endpoint references convey the information needed to address a Web service Endpoint.

Receive: The act of reading a message from a network connection and accepting it.

RM Destination: The Endpoint that Receives messages Transmitted reliably from an RM Source.

RM Protocol Header Block: One of Sequence, SequenceAcknowledgement, or AckRequested.

RM Source: The Endpoint that Transmits messages reliably to an RM Destination.

Send: The act of transferring a message from the Application Source to the RM Source for reliable transfer.

Sequence Lifecycle Message: A message that contains one of: CreateSequence, CreateSequenceResponse, CloseSequence, CloseSequenceResponse, TerminateSequence, TerminateSequenceResponse as the child element of the SOAP body element.

Sequence Traffic Messsage: A message containing a Sequence header block.

Transmit: The act of writing a message to a network connection.

2.2 Protocol Preconditions

The correct operation of the protocol requires that a number of preconditions MUST be established prior to the processing of the initial sequenced message:

2.3 Protocol Invariants

During the lifetime of a Sequence, two invariants are REQUIRED for correctness:

2.4 Example Message Exchange

Figure 2 illustrates a possible message exchange between two reliable messaging Endpoints A and B.

Frame1


  1. The protocol preconditions are established. These include policy exchange, endpoint resolution, and establishing trust.

  2. The RM Source requests creation of a new Sequence.

  3. The RM Destination creates a new Sequence and returns its unique identifier.

  4. The RM Source begins Transmitting messages in the Sequence beginning with MessageNumber 1. In the figure above, the RM Source sends 3 messages in the Sequence.

  5. The 2nd message in the Sequence is lost in transit.

  6. The 3rd message is the last in this Sequence and the RM Source includes an AckRequested header to ensure that it gets a timely SequenceAcknowledgement for the Sequence.

  7. The RM Destination acknowledges receipt of message numbers 1 and 3 as a result of receiving the RM Source's AckRequested header.

  8. The RM Source retransmits the unacknowledged message with MessageNumber 2. This is a new message from the perspective of the underlying transport, but it has the same Sequence Identifier and MessageNumber so the RM Destination can recognize it as a duplicate of the earlier message, in case the original and retransmitted messages are both Received. The RM Source includes an AckRequested header in the retransmitted message so the RM Destination will expedite an acknowledgement.

  9. The RM Destination Receives the second transmission of the message with MessageNumber 2 and acknowledges receipt of message numbers 1, 2, and 3.

  10. The RM Source Receives this Acknowledgement and sends a TerminateSequence message to the RM Destination indicating that the Sequence is completed and reclaims any resources associated with the Sequence.

  11. The RM Destination Receives the TerminateSequence message indicating that the RM Source will not be sending any more messages. The RM Destination sends a TerminateSequenceResponse message to the RM Source and and reclaims any resources associated with the Sequence.

The RM Source will expect to Receive Acknowledgements from the RM Destination during the course of a message exchange at occasions described in Section 3 below. Should an Acknowledgement not be Received in a timely fashion, the RM Source MUST re-transmit the message since either the message or the associated Acknowledgement might have been lost. Since the nature and dynamic characteristics of the underlying transport and potential intermediaries are unknown in the general case, the timing of re-transmissions cannot be specified. Additionally, over-aggressive re-transmissions have been demonstrated to cause transport or intermediary flooding which are counterproductive to the intention of providing a reliable exchange of messages. Consequently, implementers are encouraged to utilize adaptive mechanisms that dynamically adjust re-transmission time and the back-off intervals that are appropriate to the nature of the transports and intermediaries envisioned. For the case of TCP/IP transports, a mechanism similar to that described as RTTM in RFC 1323 [RTTM] SHOULD be considered.

Now that the basic model has been outlined, the details of the elements used in this protocol are now provided in Section 3.

3 RM Protocol Elements

The following sub-sections define the various RM protocol elements, and prescribe their usage by a conformant implementations.

3.1 Considerations on the Use of Extensibility Points

The following protocol elements define extensibility points at various places. Implementations MAY add child elements and/or attributes at the indicated extension points but MUST NOT contradict the semantics of the parent and/or owner, respectively. If a receiver does not recognize an extension, the receiver SHOULD ignore the extension.

3.2 Considerations on the Use of "Piggy-Backing"

Some RM header blocks may be added to messages that happen to be targeted to the same Endpoint to which those headers are to be sent (a concept often referred to as "piggy-backing"), thus saving the overhead of an additional message exchange. Reference parameters MUST be considered when determining whether two EPRs are targeted to the same Endpoint.

3.3 Composition with WS-Addressing

When the RM protocol, defined in this specification, is composed with the WS-Addressing specification, the following rules prescribe the constraints on the value of the wsa:Action header:

  1. When an Endpoint generates a message that carries an RM protocol element, that is defined in section 3 below, in the body of a SOAP envelope that Endpoint MUST include in that envelope a wsa:Action SOAP header block whose value is an IRI that is a concatenation of the WS-RM namespace URI, followed by a "/", followed by the value of the local name of the child element of the SOAP body . For example, for a Sequence creation request message as described in section 3.1 below, the value of the wsa:Action IRI would be:

http://docs.oasis-open.org/ws-rx/wsrm/200608/CreateSequence
  1. When an Endpoint generates an Acknowledgement Message that has no element content in the SOAP body, then the value of the wsa:Action IRI MUST be:

http://docs.oasis-open.org/ws-rx/wsrm/200608/SequenceAcknowledgement
  1. When an Endpoint generates an Acknowledgement Request that has no element content in the SOAP body, then the value of the wsa:Action IRI MUST be:

http://docs.oasis-open.org/ws-rx/wsrm/200608/AckRequested
  1. When an Endpoint generates an RM fault as defined in section 4 below, the value of the wsa:Action IRI MUST be as defined in section 4 below.

3.4 Sequence Creation

The RM Source MUST request creation of an outbound Sequence by sending a CreateSequence element in the body of a message to the RM Destination which in turn responds either with a message containing CreateSequenceResponse or a CreateSequenceRefused fault. The RM Source MAY include an offer to create an inbound Sequence within the CreateSequence message. This offer is either accepted or rejected by the RM Destination in the CreateSequenceResponse message.

The SOAP version used for the CreateSequence message SHOULD be used for all subsequent messages in or for that Sequence, sent by either the RM Source or the RM Destination.

The following exemplar defines the CreateSequence syntax:

<wsrm:CreateSequence ...>
    <wsrm:AcksTo> wsa:EndpointReferenceType </wsrm:AcksTo>
    <wsrm:Expires ...> xs:duration </wsrm:Expires> ?
    <wsrm:Offer ...>
        <wsrm:Identifier ...> xs:anyURI </wsrm:Identifier>
        <wsrm:Endpoint> wsa:EndpointReferenceType </wsrm:Endpoint>
        <wsrm:Expires ...> xs:duration </wsrm:Expires> ?
        <wsrm:IncompleteSequenceBehavior>
            wsrm:IncompleteSequenceBehaviorType
        </wsrm:IncompleteSequenceBehavior> ?
        ...
    </wsrm:Offer> ?
    ...
</wsrm:CreateSequence>
/wsrm:CreateSequence

This element requests creation of a new Sequence between the RM Source that sends it, and the RM Destination to which it is sent. The RM Source MUST NOT send this element as a header block. The RM Destination MUST respond either with a CreateSequenceResponse response message or a CreateSequenceRefused fault.

/wsrm:CreateSequence/wsrm:AcksTo

The RM Source MUST include this element in any CreateSequence message it sends. This element is of type wsa:EndpointReferenceType (as specified by WS-Addressing). It specifies the endpoint reference to which messages containing SequenceAcknowledgement header blocks and faults related to the created Sequence are to be sent, unless otherwise noted in this specification (for example, see Section 3.2).

Implementations MUST NOT use an endpoint reference in the AcksTo element that would prevent the sending of Sequence Acknowledgements back to the RM Source. For example, using the WS-Addressing "http://www.w3.org/2005/08/addressing/none" IRI would make it impossible for the RM Destination to ever send Sequence Acknowledgements.

/wsrm:CreateSequence/wsrm:Expires

This element, if present, of type xs:duration specifies the RM Source's requested duration for the Sequence. The RM Destination MAY either accept the requested duration or assign a lesser value of its choosing. A value of "PT0S" indicates that the Sequence will never expire. Absence of the element indicates an implied value of "PT0S".

/wsrm:CreateSequence/wsrm:Expires/@{any}

This is an extensibility mechanism to allow additional attributes, based on schemas, to be added to the element.

/wsrm:CreateSequence/wsrm:Offer

This element, if present, enables an RM Source to offer a corresponding Sequence for the reliable exchange of messages Transmitted from RM Destination to RM Source.

/wsrm:CreateSequence/wsrm:Offer/wsrm:Identifier

The RM Source MUST set the value of this element to an absolute URI (conformant with RFC3986 [URI]) that uniquely identifies the offered Sequence.

/wsrm:CreateSequence/wsrm:Offer/wsrm:Identifier/@{any}

This is an extensibility mechanism to allow additional attributes, based on schemas, to be added to the element.

/wsrm:CreateSequence/wsrm:Offer/wsrm:Endpoint

An RM Source MUST include this element, of type wsa:EndpointReferenceType (as specified by WS-Addressing). This element specifies the endpoint reference to which Sequence Lifecycle Messages, Sequence Traffic Messages, Acknowledgement Requests, and fault messages related to the offered Sequence are to be sent.

Implementations MUST NOT use an endpoint reference in the Endpoint element that would prevent the sending of Sequence Lifecycle Message, Sequence Traffic Message, etc. For example, using the WS-Addressing "http://www.w3.org/2005/08/addressing/none" IRI would make it impossible for the RM Destination to ever send Sequence Lifecycle Messages (e.g. TerminateSequence) to the RM Source for the Offered Sequence. Implementations MAY use the WS-RM anonymous URI template and doing so implies that messages will be retrieved using a mechanism such as the MakeConnection message (see section 3.7).

/wsrm:CreateSequence/wsrm:Offer/wsrm:Expires

This element, if present, of type xs:duration specifies the duration for the offered Sequence. A value of "PT0S" indicates that the offered Sequence will never expire. Absence of the element indicates an implied value of "PT0S".

/wsrm:CreateSequence/wsrm:Offer/wsrm:Expires/@{any}

This is an extensibility mechanism to allow additional attributes, based on schemas, to be added to the element.

/wsrm:CreateSequence/wsrm:Offer/wsrm:IncompleteSequenceBehavior

This element, if present, specifies the behavior that the destination will exhibit upon the closure or termination of an incomplete Sequence. For the purposes of defining the values used, the term "discard" refers to behavior equivalent to the Application Destination never processing a particular message.

A value of “DiscardEntireSequence” indicates that the entire Sequence MUST be discarded if the Sequence is closed, or terminated, when there are one or more gaps in the final SequenceAcknowledgement.

A value of “DiscardFollowingFirstGap” indicates that messages in the Sequence beyond the first gap MUST be discarded when there are one or more gaps in the final SequenceAcknowledgement.

The default value of “NoDiscard” indicates that no acknowledged messages in the Sequence will be discarded.

/wsrm:CreateSequence/wsrm:Offer/{any}

This is an extensibility mechanism to allow different (extensible) types of information, based on a schema, to be passed.

/wsrm:CreateSequence/wsrm:Offer/@{any}

This is an extensibility mechanism to allow different (extensible) types of information, based on a schema, to be passed.

/wsrm:CreateSequence/{any}

This is an extensibility mechanism to allow different (extensible) types of information, based on a schema, to be passed.

/wsrm:CreateSequence/@{any}

This is an extensibility mechanism to allow additional attributes, based on schemas, to be added to the element.

A CreateSequenceResponse is sent in the body of a response message by an RM Destination in response to receipt of a CreateSequence request message. It carries the Identifier of the created Sequence and indicates that the RM Source can begin sending messages in the context of the identified Sequence.

The following exemplar defines the CreateSequenceResponse syntax:

<wsrm:CreateSequenceResponse ...>
    <wsrm:Identifier ...> xs:anyURI </wsrm:Identifier>
    <wsrm:Expires ...> xs:duration </wsrm:Expires> ?
    <wsrm:IncompleteSequenceBehavior>
        wsrm:IncompleteSequenceBehaviorType
    </wsrm:IncompleteSequenceBehavior> ?
    <wsrm:Accept ...>
        <wsrm:AcksTo> wsa:EndpointReferenceType </wsrm:AcksTo>
        ...
    </wsrm:Accept> ?
    ...
</wsrm:CreateSequenceResponse>
/wsrm:CreateSequenceResponse

This element is sent in the body of the response message in response to a CreateSequence request message. It indicates that the RM Destination has created a new Sequence at the request of the RM Source. The RM Destination MUST NOT send this element as a header block.

/wsrm:CreateSequenceResponse/wsrm:Identifier

The RM Destination MUST include this element within any CreateSequenceResponse message it sends. The RM Destination MUST set the value of this element to the absolute URI (conformant with RFC3986) that uniquely identifies the Sequence that has been created by the RM Destination.

/wsrm:CreateSequenceResponse/wsrm:Identifier/@{any}

This is an extensibility mechanism to allow additional attributes, based on schemas, to be added to the element.

/wsrm:CreateSequenceResponse/wsrm:Expires

This element, if present, of type xs:duration accepts or refines the RM Source's requested duration for the Sequence. It specifies the amount of time after which any resources associated with the Sequence SHOULD be reclaimed thus causing the Sequence to be silently teriminated. At the RM Destination this duration is measured from a point proximate to Sequence creation and at the RM Source this duration is measured from a point approximate to the successful processing of the CreateSequenceResponse. A value of "PT0S" indicates that the Sequence will never expire. Absence of the element indicates an implied value of "PT0S". The RM Destination MUST set the value of this element to be equal to or less than the value requested by the RM Source in the corresponding CreateSequence message.

/wsrm:CreateSequenceResponse/wsrm:Expires/@{any}

This is an extensibility mechanism to allow additional attributes, based on schemas, to be added to the element.

/wsrm:CreateSequenceResponse/wsrm:IncompleteSequenceBehavior

This element, if present, specifies the behavior that the destination will exhibit upon the closure or termination of an incomplete Sequence. For the purposes of defining the values used, the term "discard" refers to behavior equivalent to the Application Destination never processing a particular message.

A value of “DiscardEntireSequence” indicates that the entire Sequence MUST be discarded if the Sequence is closed, or terminated, when there are one or more gaps in the final SequenceAcknowledgement.

A value of “DiscardFollowingFirstGap” indicates that messages in the Sequence beyond the first gap MUST be discarded when there are one or more gaps in the final SequenceAcknowledgement.

The default value of “NoDiscard” indicates that no acknowledged messages in the Sequence will be discarded.

/wsrm:CreateSequenceResponse/wsrm:Accept

This element, if present, enables an RM Destination to accept the offer of a corresponding Sequence for the reliable exchange of messages Transmitted from RM Destination to RM Source.

Note: If a CreateSequenceResponse is returned without a child Accept in response to a CreateSequence that did contain a child Offer, then the RM Source MAY immediately reclaim any resources associated with the unused offered Sequence.

/wsrm:CreateSequenceResponse/wsrm:Accept/wsrm:AcksTo

The RM Destination MUST include this element, of type wsa:EndpointReferenceType (as specified by WS-Addressing). It specifies the endpoint reference to which messages containing SequenceAcknowledgement header blocks and faults related to the created Sequence are to be sent, unless otherwise noted in this specification (for example, see Section 3.2).

Implementations MUST NOT use an endpoint reference in the AcksTo element that would prevent the sending of Sequence Acknowledgements back to the RM Source. For example, using the WS-Addressing "http://www.w3.org/2005/08/addressing/none" IRI would make it impossible for the RM Destination to ever send Sequence Acknowledgements.

/wsrm:CreateSequenceResponse/wsrm:Accept/{any}

This is an extensibility mechanism to allow different (extensible) types of information, based on a schema, to be passed.

/wsrm:CreateSequenceResponse/wsrm:Accept/@{any}

This is an extensibility mechanism to allow different (extensible) types of information, based on a schema, to be passed.

/wsrm:CreateSequenceResponse/{any}

This is an extensibility mechanism to allow different (extensible) types of information, based on a schema, to be passed.

/wsrm:CreateSequenceResponse/@{any}

This is an extensibility mechanism to allow additional attributes, based on schemas, to be added to the element.

3.5 Closing A Sequence

There are times during the use of an RM Sequence that the RM Source or RM Destination will wish to discontinue using a Sequence. Simply terminating the Sequence discards the state managed by the RM Destination, leaving the RM Source unaware of the final ranges of messages that were successfully transferred to the RM Destination. To ensure that the Sequence ends with a known final state either the RM Source or RM Destination MAY choose to close the Sequence before terminating it.

If the RM Source wishes to close the Sequence, then it sends a CloseSequence element, in the body of a message, to the RM Destination. This message indicates that the RM Destination MUST NOT accept any new messages for the specified Sequence, other than those already accepted at the time the CloseSequence element is interpreted by the RM Destination. Upon receipt of this message, or subsequent to the RM Destination closing the Sequence of its own volition, the RM Destination MUST include a final SequenceAcknowledgement (within which the RM Destination MUST include the Final element) header block on any messages associated with the Sequence destined to the RM Source, including the CloseSequenceResponse message or on any Sequence fault Transmitted to the RM Source.

While the RM Destination MUST NOT accept any new messages for the specified Sequence it MUST still process Sequence Lifecyle Messages and Acknowledgement Requests. For example, it MUST respond to AckRequested, TerminateSequence as well as CloseSequence messages. Note, subsequent CloseSequence messages have no effect on the state of the Sequence.

In the case where the RM Destination wishes to discontinue use of a Sequence it is RECOMMENDED that it close the Sequence. Please see Final and the SequenceClosed fault. Whenever possible the SequenceClosed fault SHOULD be used in place of the SequenceTerminated fault to allow the RM Source to still Receive Acknowledgements.

The following exemplar defines the CloseSequence syntax:

<wsrm:CloseSequence ...>
    <wsrm:Identifier ...> xs:anyURI </wsrm:Identifier>
    ...
</wsrm:CloseSequence>
/wsrm:CloseSequence

This element is sent by an RM Source to indicate that the RM Destination MUST NOT accept any new messages for this Sequence. A SequenceClosed fault MUST be generated by the RM Destination when it Receives a message for a Sequence that is already closed.

/wsrm:CloseSequence/wsrm:Identifier

The RM Source MUST include this element in any CloseSequence messages it sends. The RM Source MUST set the value of this element to the absolute URI (conformant with RFC3986) of the Sequence that is being closed.

/wsrm:CloseSequence/wsrm:Identifier/@{any}

This is an extensibility mechanism to allow additional attributes, based on schemas, to be added to the element.

/wsrm:CloseSequence/{any}

This is an extensibility mechanism to allow different (extensible) types of information, based on a schema, to be passed.

/wsrm:CloseSequence@{any}

This is an extensibility mechanism to allow additional attributes, based on schemas, to be added to the element.

A CloseSequenceResponse is sent in the body of a response message by an RM Destination in response to receipt of a CloseSequence request message. It indicates that the RM Destination has closed the Sequence.

The following exemplar defines the CloseSequenceResponse syntax:

<wsrm:CloseSequenceResponse ...>
    <wsrm:Identifier ...> xs:anyURI </wsrm:Identifier>
    ...
</wsrm:CloseSequenceResponse>
/wsrm:CloseSequenceResponse

This element is sent in the body of a response message by an RM Destination in response to receipt of a CloseSequence request message. It indicates that the RM Destination has closed the Sequence.

/wsrm:CloseSequenceResponse/wsrm:Identifier

The RM Destination MUST include this element in any CloseSequenceResponse message it sends. The RM Destination MUST set the value of this element to the absolute URI (conformant with RFC3986) of the Sequence that is being closed.

/wsrm:CloseSequenceResponse/wsrm:Identifier/@{any}

This is an extensibility mechanism to allow additional attributes, based on schemas, to be added to the element.

/wsrm:CloseSequenceResponse/{any}

This is an extensibility mechanism to allow different (extensible) types of information, based on a schema, to be passed.

/wsrm:CloseSequenceResponse@{any}

This is an extensibility mechanism to allow additional attributes, based on schemas, to be added to the element.

3.6 Sequence Termination

When the RM Source has completed its use of the Sequence it sends a TerminateSequence element, in the body of a message, to the RM Destination to indicate that the Sequence is complete and that it will not be sending any further messages related to the Sequence. The RM Destination can safely reclaim any resources associated with the Sequence upon receipt of the TerminateSequence message. Under normal usage the RM Source will complete its use of the Sequence when all of the messages in the Sequence have been acknowledged. However, the RM Source is free to Terminate or Close a Sequence at any time regardless of the acknowledgement state of the messages.

The following exemplar defines the TerminateSequence syntax:

<wsrm:TerminateSequence ...>
    <wsrm:Identifier ...> xs:anyURI </wsrm:Identifier>
    ...
</wsrm:TerminateSequence>
/wsrm:TerminateSequence

This element is sent by an RM Source to indicate it has completed its use of the Sequence. It indicates that the RM Destination can safely reclaim any resources related to the identified Sequence. The RM Source MUST NOT send this element as a header block. The RM Source MAY retransmit this element. Once this element is sent, other than this element, the RM Source MUST NOT send any additional message to the RM Destination referencing this Sequence.

/wsrm:TerminateSequence/wsrm:Identifier

The RM Source MUST include this element in any TerminateSequence message it sends. The RM Source MUST set the value of this element to the absolute URI (conformant with RFC3986) of the Sequence that is being terminated.

/wsrm:TerminateSequence/wsrm:Identifier/@{any}

This is an extensibility mechanism to allow additional attributes, based on schemas, to be added to the element.

/wsrm:TerminateSequence/{any}

This is an extensibility mechanism to allow different (extensible) types of information, based on a schema, to be passed.

/wsrm:TerminateSequence/@{any}

This is an extensibility mechanism to allow additional attributes, based on schemas, to be added to the element.

A TerminateSequenceResponse is sent in the body of a response message by an RM Destination in response to receipt of a TerminateSequence request message. It indicates that the RM Destination has terminated the Sequence.

The following exemplar defines the TerminateSequenceResponse syntax:

<wsrm:TerminateSequenceResponse ...>
    <wsrm:Identifier ...> xs:anyURI </wsrm:Identifier>
    ...
</wsrm:TerminateSequenceResponse>
/wsrm:TerminateSequenceResponse

This element is sent in the body of a response message by an RM Destination in response to receipt of a TerminateSequence request message. It indicates that the RM Destination has terminated the Sequence. The RM Destination MUST NOT send this element as a header block.

/wsrm:TerminateSequenceResponse/wsrm:Identifier

The RM Destination MUST include this element in any TerminateSequenceResponse message it sends. The RM Destination MUST set the value of this element to the absolute URI (conformant with RFC3986) of the Sequence that is being terminated.

/wsrm:TerminateSequenceResponse/wsrm:Identifier/@{any}

This is an extensibility mechanism to allow additional attributes, based on schemas, to be added to the element.

/wsrm:TerminateSequenceResponse/{any}

This is an extensibility mechanism to allow different (extensible) types of information, based on a schema, to be passed.

/wsrm:TerminateSequenceResponse/@{any}

This is an extensibility mechanism to allow additional attributes, based on schemas, to be added to the element.

On receipt of a TerminateSequence message an RM Destination MUST respond with a corresponding TerminateSequenceResponse message or generate a fault UnknownSequenceFault if the Sequence is not known.

3.7 Sequences

The RM protocol uses a Sequence header block to track and manage the reliable transfer of messages. The RM Source MUST include a Sequence header block in all messages for which reliable transfer is REQUIRED. The RM Source MUST identify Sequences with unique Identifier elements and the RM Source MUST assign each message within a Sequence a MessageNumber element that increments by 1 from an initial value of 1. These values are contained within a Sequence header block accompanying each message being transferred in the context of a Sequence.

The RM Source MUST NOT include more than one Sequence header block in any message.

A following exemplar defines its syntax:

<wsrm:Sequence ...>
    <wsrm:Identifier ...> xs:anyURI </wsrm:Identifier>
    <wsrm:MessageNumber> wsrm:MessageNumberType </wsrm:MessageNumber>
    ...
</wsrm:Sequence>

The following describes the content model of the Sequence header block.

/wsrm:Sequence

This protocol element associates the message in which it is contained with a previously established RM Sequence. It contains the Sequence's unique identifier and the containing message's ordinal position within that Sequence. The RM Destination MUST understand the Sequence header block. The RM Source MUST assign a mustUnderstand attribute with a value 1/true (from the namespace corresponding to the version of SOAP to which the Sequence SOAP header block is bound) to the Sequence header block element.

/wsrm:Sequence/wsrm:Identifier

An RM Source that includes a Sequence header block in a SOAP envelope MUST include this element in that header block. The RM Source MUST set the value of this element to the absolute URI (conformant with RFC3986) that uniquely identifies the Sequence.

/wsrm:Sequence/wsrm:Identifier/@{any}

This is an extensibility mechanism to allow additional attributes, based on schemas, to be added to the element.

/wsrm:Sequence/wsrm:MessageNumber

The RM Source MUST include this element within any Sequence headers it creates. This element is of type MessageNumberType. It represents the ordinal position of the message within a Sequence. Sequence message numbers start at 1 and monotonically increase by 1 throughout the Sequence. See Section 4.5 for Message Number Rollover fault.

/wsrm:Sequence/{any}

This is an extensibility mechanism to allow different types of information, based on a schema, to be passed.

/wsrm:Sequence/@{any}

This is an extensibility mechanism to allow additional attributes, based on schemas, to be added to the element.

The following example illustrates a Sequence header block.

<wsrm:Sequence>
    <wsrm:Identifier>http://example.com/abc</wsrm:Identifier>
    <wsrm:MessageNumber>10</wsrm:MessageNumber>
</wsrm:Sequence>

3.8 Request Acknowledgement

The purpose of the AckRequested header block is to signal to the RM Destination that the RM Source is requesting that a SequenceAcknowledgement be sent.

The RM Source MAY request an Acknowledgement Message from the RM Destination at any time by including an AckRequested header block in any message targeted to the RM Destination. An RM Destination that Receives a message that contains an AckRequested header block MUST send a message containing a SequenceAcknowledgement header block to the AcksTo endpoint reference (see Section 3.1) for a known Sequence or else generate an UnknownSequence fault. If a non-mustUnderstand fault occurs when processing an RM header that was piggy-backed on another message, a fault MUST be generated, but the processing of the original message MUST NOT be affected. It is RECOMMENDED that the RM Destination return a AcknowledgementRange or None element instead of a Nack element (see Section 3.6).

The following exemplar defines its syntax:

<wsrm:AckRequested ...>
    <wsrm:Identifier ...> xs:anyURI </wsrm:Identifier>
    ...
</wsrm:AckRequested>
/wsrm:AckRequested

This element requests an Acknowledgement for the identified Sequence.

/wsrm:AckRequested/wsrm:Identifier

An RM Source that includes a AckRequested header block in a SOAP envelope MUST include this element in that header block. The RM Source MUST set the value of this element to the absolute URI, (conformant with RFC3986), that uniquely identifies the Sequence to which the request applies.

/wsrm:AckRequested/wsrm:Identifier/@{any}

This is an extensibility mechanism to allow additional attributes, based on schemas, to be added to the element.

/wsrm:AckRequested/{any}

This is an extensibility mechanism to allow different (extensible) types of information, based on a schema, to be passed.

/wsrm:AckRequested/@{any}

This is an extensibility mechanism to allow additional attributes, based on schemas, to be added to the element.

3.9 Sequence Acknowledgement

The RM Destination informs the RM Source of successful message receipt using a SequenceAcknowledgement header block. The RM Destination MAY Transmit the SequenceAcknowledgement header block independently or it MAY include the SequenceAcknowledgement header block on any message targeted to the AcksTo EPR. Acknowledgements can be explicitly requested using the AckRequested directive (see Section 3.5). If a non-mustUnderstand fault occurs when processing an RM header that was piggy-backed on another message, a fault MUST be generated, but the processing of the original message MUST NOT be affected.

A RM Destination MAY include a SequenceAcknowledgement header block on any SOAP envelope targetted to the endpoint referenced by the AcksTo EPR.

During creation of a Sequence the RM Source MAY specify the WS-Addressing anonymous IRI as the address of the AcksTo EPR for that Sequence. When the RM Source specifies the WS-Addressing anonymous IRI as the address of the AcksTo EPR, the RM Destination MUST Transmit any SequenceAcknowledgement headers for the created Sequence in a SOAP envelope to be Transmitted on the protocol binding-specific channel. Such a channel is provided by the context of a Received message containing a SOAP envelope that contains a Sequence header block and/or a AckRequested header block for that same Sequence identifier.

The following exemplar defines its syntax:

<wsrm:SequenceAcknowledgement ...>
    <wsrm:Identifier ...> xs:anyURI </wsrm:Identifier>
    [ [ [ <wsrm:AcknowledgementRange ...
            Upper="wsrm:MessageNumberType"
            Lower="wsrm:MessageNumberType"/> +
        | <wsrm:None/> ]
        <wsrm:Final/> ? ]
    | <wsrm:Nack> wsrm:MessageNumberType </wsrm:Nack> + ]
 
    ...
</wsrm:SequenceAcknowledgement>

The following describes the content model of the SequenceAcknowledgement header block.

/wsrm:SequenceAcknowledgement

This element contains the Sequence Acknowledgement information.

/wsrm:SequenceAcknowledgement/wsrm:Identifier

An RM Destination that includes a SequenceAcknowledgement header block in a SOAP envelope MUST include this element in that header block. The RM Destination MUST set the value of this element to the absolute URI (conformant with RFC3986) that uniquely identifies the Sequence. The RM Destination MUST NOT include multiple SequenceAcknowledgement header blocks that share the same value for Identifier within the same SOAP envelope.

/wsrm:SequenceAcknowledgement/wsrm:Identifier/@{any}

This is an extensibility mechanism to allow additional attributes, based on schemas, to be added to the element.

/wsrm:SequenceAcknowledgement/wsrm:AcknowledgementRange

The RM Destination MAY include one or more instances of this element within a SequenceAcknowledgement header block. It contains a range of Sequence MessageNumbers successfully accepted by the RM Destination. The ranges SHOULD NOT overlap. The RM Destination MUST NOT include this element if a sibling Nack or None element is also present as a child of SequenceAcknowledgement.

/wsrm:SequenceAcknowledgement/wsrm:AcknowledgementRange/@Upper

The RM Destination MUST set the value of this attribute equal to the message number of the highest contiguous message in a Sequence range accepted by the RM Destination.

/wsrm:SequenceAcknowledgement/wsrm:AcknowledgementRange/@Lower

The RM Destination MUST set the value of this attribute equal to the message number of the lowest contiguous message in a Sequence range accepted by the RM Destination.

/wsrm:SequenceAcknowledgement/wsrm:AcknowledgementRange/@{any}

This is an extensibility mechanism to allow additional attributes, based on schemas, to be added to the element.

/wsrm:SequenceAcknowledgement/wsrm:None

The RM Destination MUST include this element within a SequenceAcknowledgement header block if the RM Destination has not accepted any messages for the specified Sequence. The RM Destination MUST NOT include this element if a sibling AcknowledgementRange or Nack element is also present as a child of the SequenceAcknowledgement.

/wsrm:SequenceAcknowledgement/wsrm:Final

The RM Destination MAY include this element within a SequenceAcknowledgement header block. This element indicates that the RM Destination is not receiving new messages for the specified Sequence. The RM Source can be assured that the ranges of messages acknowledged by this SequenceAcknowledgement header block will not change in the future. The RM Destination MUST include this element when the Sequence is closed. The RM Destination MUST NOT include this element when sending a Nack; it can only be used when sending AcknowledgementRange elements or a None.

/wsrm:SequenceAcknowledgement/wsrm:Nack

The RM Destination MAY include this element within a SequenceAcknowledgement header block. If used, the RM Destination MUST set the value of this element to a MessageNumberType representing the MessageNumber of an unreceived message in a Sequence. The RM Destination MUST NOT include a Nack element if a sibling AcknowledgementRange or None element is also present as a child of SequenceAcknowledgement. Upon the receipt of a Nack, an RM Source SHOULD retransmit the message identified by the Nack. The RM Destination MUST NOT issue a SequenceAcknowledgement containing a Nack for a message that it has previously acknowledged within a AcknowledgementRange. The RM Source SHOULD ignore a SequenceAcknowledgement containing a Nack for a message that has previously been acknowledged within a AcknowledgementRange.

/wsrm:SequenceAcknowledgement/{any}

This is an extensibility mechanism to allow different (extensible) types of information, based on a schema, to be passed.

/wsrm:SequenceAcknowledgement/@{any}

This is an extensibility mechanism to allow additional attributes, based on schemas, to be added to the element.

The following examples illustrate SequenceAcknowledgement elements:

<wsrm:SequenceAcknowledgement> 
    <wsrm:Identifier>http://example.com/abc</wsrm:Identifier>
    <wsrm:AcknowledgementRange Upper="10" Lower="1"/>
</wsrm:SequenceAcknowledgement>
<wsrm:SequenceAcknowledgement> 
    <wsrm:Identifier>http://example.com/abc</wsrm:Identifier>
    <wsrm:AcknowledgementRange Upper="2" Lower="1"/>
    <wsrm:AcknowledgementRange Upper="6" Lower="4"/>
    <wsrm:AcknowledgementRange Upper="10" Lower="8"/>
</wsrm:SequenceAcknowledgement>
<wsrm:SequenceAcknowledgement> 
    <wsrm:Identifier>http://example.com/abc</wsrm:Identifier>
    <wsrm:Nack>3</wsrm:Nack>
</wsrm:SequenceAcknowledgement>

3.10 MakeConnection

When an Endpoint is not directly addressable (e.g. behind a firewall or not able to allow incoming connections), an anonymous URI in the EPR address property can indicate such an Endpoint. The WS-Addressing anonymous URI is one such anonymous URI. This specification defines a URI template (the WS-RM anonymous URI) which may be used to uniquely identify anonymous Endpoints.

http://docs.oasis-open.org/ws-rx/wsrm/200608/anonymous?id={uuid}

This URI template in an EPR indicates a protocol-specific back-channel will be established through a mechanism such as MakeConnection, defined below. When using this URI template, “{uuid}” MUST be replaced by a UUID value as defined by RFC 4122[UUID]. This UUID value uniquely distinguishes the Endpoint. A sending Endpoint SHOULD Transmit messages at Endpoints identified with the URI template using a protocol-specific back-channel, including but not limited to those established with a MakeConnection message. Note, this URI is semantically similar to the WS-Addressing anonymous URI if a protocol-specific back-channel is available.

The MakeConnection is a one-way operation that establishes a contextualized back-channel for the transmission of messages according to matching criteria (defined below). In the non-faulting case, if no matching message is available then no SOAP envelopes will be returned on the back-channel. A common usage will be a client RM Destination sending MakeConnection to a server RM Source for the purpose of receiving asynchronous response messages.

The following exemplar defines the MakeConnection syntax:

<wsrm:MakeConnection ...> 
    <wsrm:Identifier ...> xs:anyURI </wsrm:Identifier> ?
    <wsrm:Address ...> xs:anyURI </wsrm:Address> ?
    ... 
</wsrm:MakeConnection>
/wsrm:MakeConnection

This element allows the sender to create a transport-specific back-channel that can be used to return a message that matches the selection criteria. Endpoints MUST NOT send this element as a header block.

/wsrm:MakeConnection/wsrm:Identifier

This element specifies the WS-RM Sequence Identifier that establishes the context for the transport-specific back-channel. The Sequence Identifier should be compared with the Sequence Identifiers associated with the messages held by the sending Endpoint, and if there is a matching message it will be returned. If this element is omitted from the message then the Address MUST be included in the message.

/wsrm:MakeConnection/wsrm:Identifier/@{any}

This is an extensibility mechanism to allow additional attributes, based on schemas, to be added to the element.

/wsrm:MakeConnection/wsrm:Address

This element specifies the URI (wsa:Address) of the initiating Endpoint. Endpoints MUST NOT return messages on the transport-specific back-channel unless they have been addressed to this URI. This Address property and a message’s WS-Addressing destination property are considered identical when they are exactly the same character-for-character. Note that URIs which are not identical in this sense may in fact be functionally equivalent. Examples include URI references which differ only in case, or which are in external entities which have different effective base URIs. If this element is omitted from the message then the Identifier MUST be included in the message.

/wsrm:MakeConnection/wsrm:Address/@{any}

This is an extensibility mechanism to allow additional attributes, based on schemas, to be added to the element.

/wsrm:MakeConnection/{any}

This is an extensibility mechanism to allow different (extensible) types of information, based on a schema, to be passed. This allows fine-tuning of the messages to be returned, additional selection criteria included here are logically ANDed with the Address and/or Identifier. If an extension is not supported by the Endpoint then it should return a UnsupportedSelection fault.

/wsrm:MakeConnection/@{any}

This is an extensibility mechanism to allow additional attributes, based on schemas, to be added to the element.

If both Identifier and Address are present, then the Endpoint processing the MakeConnection message MUST insure that any SOAP Envelope flowing on the backchannel MUST be associated with the given Sequence and MUST be addressed to the given URI.

The management of messages that are awaiting the establishment of a back-channel to their receiving Endpoint is an implementation detail that is outside the scope of this specification. Note, however, that these messages form a class of asynchronous messages that is not dissimilar from “ordinary” asynchronous messages that are waiting for the establishment of a connection to their destination Endpoints.

This specification places no constraint on the types of messages that can be returned on the transport-specific back-channel. As in an asynchronous environment, it is up to the recipient of the MakeConnection message to decide which messages are appropriate for transmission to any particular Endpoint. However, the Endpoint processing the MakeConnection message MUST insure that the messages match the selection criteria as specified by the child elements of the MakeConnection element.

3.11 MessagePending

When MakeConnection is used, and a message is returned on the transport-specific back-channel, the MessagePending header SHOULD be included on the returned message as an indicator whether there are additional messages waiting to be retrieved using the same selection criteria that was specified in the MakeConnection element.

The following exemplar defines the MessagePending syntax:

<wsrm:MessagePending pending="xs:boolean" ...>
    ...
</wsrm:MessagePending>
/wsrm:MessagePending

This element indicates whether additional messages are waiting to be retrieved.

/wsrm:MessagePending@pending

This attribute, when set to "true", indicates that there is at least one message waiting to be retrieved. When this attribute is set to "false" it indicates there are currently no messages waiting to be retrieved.

/wsrm:MessagePending/{any}

This is an extensibility mechanism to allow different (extensible) types of information, based on a schema, to be passed.

/wsrm:MessagePending/@{any}

This is an extensibility mechanism to allow additional attributes, based on schemas, to be added to the element.

The absence of the MessagePending header has no implication as to whether there are additional messages waiting to be retrieved.

4 Faults

Faults for the CreateSequence message exchange are treated as defined in WS-Addressing. Create Sequence Refused is a possible fault reply for this operation. Unknown Sequence is a fault generated by Endpoints when messages carrying RM header blocks targeted at unrecognized or terminated Sequences are detected. WSRM Required is a fault generated an RM Destination that requires the use of WS-RM on a Received message that did not use the protocol. All other faults in this section relate to known Sequences. RM Destinations that generate Sequence faults SHOULD send those faults to the same [destination] as Acknowledgement Messages.

Entities that generate WS-ReliableMessaging faults MUST include as the [action] property the default fault action IRI defined below. The value from the W3C Recommendation is below for informational purposes:

http://docs.oasis-open.org/ws-rx/wsrm/200608/fault

The faults defined in this section are generated if the condition stated in the preamble is met. Fault handling rules are defined in section 6 of WS-Addressing SOAP Binding.

The definitions of faults use the following properties:

[Code] The fault code.

[Subcode] The fault subcode.

[Reason] The English language reason element.

[Detail] The detail element(s). If absent, no detail element is defined for the fault. If more than one detail element is defined for a fault, implementations MUST include the elements in the order that they are specified.

Entities that generate WS-ReliableMessaging faults MUST set the [Code] property to either "Sender" or "Receiver". These properties are serialized into text XML as follows:

SOAP Version

Sender

Receiver

SOAP 1.1

S11:Client

S11:Server

SOAP 1.2

S:Sender

S:Receiver

The properties above bind to a SOAP 1.2 fault as follows:

<S:Envelope>
 <S:Header>
   <wsa:Action>
      http://docs.oasis-open.org/ws-rx/wsrm/200608/fault
   </wsa:Action>
   <!-- Headers elided for clarity.  -->
 </S:Header>
 <S:Body>
  <S:Fault>
   <S:Code>
     <S:Value> [Code] </S:Value>
     <S:Subcode>
      <S:Value> [Subcode] </S:Value>
     </S:Subcode>
   </S:Code>
   <S:Reason>
     <S:Text xml:lang="en"> [Reason] </S:Text>
   </S:Reason>
   <S:Detail>
     [Detail]
     ...
   </S:Detail>    
  </S:Fault>
 </S:Body>
</S:Envelope>

The properties above bind to a SOAP 1.1 fault as follows when the fault is triggered by processing an RM header block:

<S11:Envelope>
 <S11:Header>
   <wsrm:SequenceFault> 
     <wsrm:FaultCode> wsrm:FaultCodes </wsrm:FaultCode>  
     <wsrm:Detail> [Detail] </wsrm:Detail>
     ... 
   </wsrm:SequenceFault>    
   <!-- Headers elided for clarity.  -->
 </S11:Header>
 <S11:Body>
  <S11:Fault>
   <faultcode> [Code] </faultcode>
   <faultstring> [Reason] </faultstring>
  </S11:Fault>
 </S11:Body>
</S11:Envelope>

The properties bind to a SOAP 1.1 fault as follows when the fault is generated as a result of processing a CreateSequence request message:

<S11:Envelope>
 <S11:Body>
  <S11:Fault>
   <faultcode> [Subcode] </faultcode>
   <faultstring> [Reason] </faultstring>
  </S11:Fault>
 </S11:Body>
</S11:Envelope>

4.1 SequenceFault Element

The purpose of the SequenceFault element is to carry the specific details of a fault generated during the reliable messaging specific processing of a message belonging to a Sequence. WS-ReliableMessaging nodes MUST use the SequenceFault container only in conjunction with the SOAP 1.1 fault mechanism. WS-ReliableMessaging nodes MUST NOT use the SequenceFault container in conjunction with the SOAP 1.2 binding.

The following exemplar defines its syntax:

<wsrm:SequenceFault ...>
  <wsrm:FaultCode> wsrm:FaultCodes </wsrm:FaultCode> 
  <wsrm:Detail> ... </wsrm:Detail> ?
  ...
</wsrm:SequenceFault>

The following describes the content model of the SequenceFault element.

/wsrm:SequenceFault

This is the element containing Sequence information for WS-ReliableMessaging

/wsrm:SequenceFault/wsrm:FaultCode

WS-ReliableMessaging nodes that generate a SequenceFault MUST set the value of this element to a qualified name from the set of fault [Subcodes] defined below.

/wsrm:SequenceFault/wsrm:Detail

This element, if present, carries application specific error information related to the fault being described.

/wsrm:SequenceFault/wsrm:Detail/{any}

The application specific error information related to the fault being described.

/wsrm:SequenceFault/wsrm:Detail/@{any}

The application specific error information related to the fault being described.

/wsrm:SequenceFault/{any}

This is an extensibility mechanism to allow different (extensible) types of information, based on a schema, to be passed.

/wsrm:SequenceFault/@{any}

This is an extensibility mechanism to allow additional attributes, based on schemas, to be added to the element.

4.2 Sequence Terminated

The Endpoint that generates this fault SHOULD make every reasonable effort to notify the corresponding Endpoint of this decision.

Properties:

[Code] Sender or Receiver

[Subcode] wsrm:SequenceTerminated

[Reason] The Sequence has been terminated due to an unrecoverable error.

[Detail]

<wsrm:Identifier ...> xs:anyURI </wsrm:Identifier>

Generated by

Condition

Action Upon Generation

Action Upon Receipt

RM Source or RM Destination.

Encountering an unrecoverable condition or detection of violation of the protocol.

Sequence termination.

MUST terminate the Sequence if not otherwise terminated.

4.3 Unknown Sequence

Properties:

[Code] Sender

[Subcode] wsrm:UnknownSequence

[Reason] The value of wsrm:Identifier is not a known Sequence identifier.

[Detail]

<wsrm:Identifier ...> xs:anyURI </wsrm:Identifier>

Generated by

Condition

Action Upon Generation

Action Upon Receipt

RM Source or RM Destination.

In response to a message containing an unknown or terminated Sequence identifier.

None.

MUST terminate the Sequence if not otherwise terminated.

4.4 Invalid Acknowledgement

An example of when this fault is generated is when a message is Received by the RM Source containing a SequenceAcknowledgement covering messages that have not been sent.

[Code] Sender

[Subcode] wsrm:InvalidAcknowledgement

[Reason] The SequenceAcknowledgement violates the cumulative Acknowledgement invariant.

[Detail]

<wsrm:SequenceAcknowledgement ...> ... </wsrm:SequenceAcknowledgement>

Generated by

Condition

Action Upon Generation

Action Upon Receipt

RM Source.

In response to a SequenceKnowledgement that violate the invariants stated in 2.3 or any of the requirements in 3.6 about valid combinations of AckRange, Nack and None in a single SequenceAcknowledgement element or with respect to already Received such elements.

Unspecified.

Unspecified.

4.5 Message Number Rollover

If the condition listed below is reached, the RM Destination MUST generate this fault.

Properties:

[Code] Sender

[Subcode] wsrm:MessageNumberRollover

[Reason] The maximum value for wsrm:MessageNumber has been exceeded.

[Detail]

<wsrm:Identifier ...> xs:anyURI </wsrm:Identifier>
<wsrm:MaxMessageNumber> wsrm:MessageNumberType </wsrm:MaxMessageNumber>

Generated by

Condition

Action Upon Generation

Action Upon Receipt

RM Destination.

Message number in /wsrm:Sequence/wsrm:MessageNumber of a Received message exceeds the internal limitations of an RM Destination or reaches the maximum value of 9,223,372,036,854,775,807.

RM Desi nation SHOULD continue to accept undelivered messages until the Sequence is closed or terminated.

RM Source SHOULD continue to retransmit undelivered messages until the Sequence is closed or terminated.

4.6 Create Sequence Refused

Properties:

[Code] Sender

[Subcode] wsrm:CreateSequenceRefused

[Reason] The create Sequence request has been refused by the RM Destination.

[Detail]

xs:any

Generated by

Condition

Action Upon Generation

Action Upon Receipt

RM Destination.

In response to a CreateSequence message when the RM Destination does not wish to create a new Sequence.

Unspecified.

Sequence terminated.

4.7 Sequence Closed

This fault is generated by an RM Destination to indicate that the specified Sequence has been closed. This fault MUST be generated when an RM Destination is asked to accept a message for a Sequence that is closed or when an RM Destination is asked to close a Sequence that is already closed.

Properties:

[Code] Sender

[Subcode] wsrm:SequenceClosed

[Reason] The Sequence is closed and can not accept new messages.

[Detail]

<wsrm:Identifier...> xs:anyURI </wsrm:Identifier>

Generated by

Condition

Action Upon Generation

Action Upon Receipt

RM Destination.

In response to a message that belongs to a Sequence that is already closed.

Unspecified.

Sequence closed.

4.8 WSRM Required

If an RM Destination requires the use of WS-RM, this fault is generated when it Receives an incoming message that did not use this protocol.

Properties:

[Code] Sender

[Subcode] wsrm:WSRMRequired

[Reason] The RM Destination requires the use of WSRM.

[Detail]

xs:any

Generated by

Condition

Action Upon Generation

Action Upon Receipt

RM Destination.

On receipt of a message that does not use this protocol and for which this protocol is required.

Unspecified.

Unspecified.

4.9 Unsupported Selection

The QName of the unsupported element(s) are included in the detail.

Properties:

[Code] Receiver

[Subcode] wsrm:UnsupportedSelection

[Reason] The extension element used in the message selection is not supported by the RM Source

[Detail]

<wsrm:UnsupportedElement> xs:QName </wsrm:UnsupportedElement>+

Generated by

Condition

Action Upon Generation

Action Upon Receipt

RM Source or RM Destination.

In response to a MakeConnection message containing a selection criteria in the extensibility section of the message that is not support.ed

Unspecified.

Unspecified.

5 Security Threats and Countermeasures

This specification considers two sets of security requirements, those of the applications that use the WS-RM protocol and those of the protocol itself.

This specification makes no assumptions about the security requirements of the applications that use WS-RM. However, once those requirements have been satisfied within a given operational context, the addition of WS-RM to this operational context should not undermine the fulfillment of those requirements; the use of WS-RM should not create additional attack vectors within an otherwise secure system.

There are many other security concerns that one may need to consider when implementing or using this protocol. The material below should not be considered as a "check list". Implementers and users of this protocol are urged to perform a security analysis to determine their particular threat profile and the appropriate responses to those threats.

Implementers are also advised that there is a core tension between security and reliable messaging that can be problematic if not addressed by implementations; one aspect of security is to prevent message replay but one of the invariants of this protocol is to resend messages until they are acknowledged. Consequently, if the security sub-system processes a message but a failure occurs before the reliable messaging sub-system Receives that message, then it is possible (and likely) that the security sub-system will treat subsequent copies as replays and discard them. At the same time, the reliable messaging sub-system will likely continue to expect and even solicit the missing message(s). Care should be taken to avoid and prevent this condition.

5.1 Threats and Countermeasures

The primary security requirement of this protocol is to protect the specified semantics and protocol invariants against various threats. The following sections describe several threats to the integrity and operation of this protocol and provide some general outlines of countermeasures to those threats. Implementers and users of this protocol should keep in mind that all threats are not necessarily applicable to all operational contexts.

5.1.1 Integrity Threats

In general, any mechanism which allows an attacker to alter the information in a Sequence Traffic Message, Sequence Lifecycle Message, Acknowledgement Messages, Acknowledgement Request, or Sequence-related fault, or which allows an attacker to alter the correlation of a RM Protocol Header Block to its intended message represents a threat to the WS-RM protocol.

For example, if an attacker is able to swap Sequence headers on messages in transit between the RM Source and RM Destination then they have undermined the implementation's ability to guarantee the first invariant described in Section 2.3. The result is that there is no way of guaranteeing that messages will be Delivered to the Application Destination in the same order that they were sent by the Application Source.

5.1.1.1 Countermeasures

Integrity threats are generally countered via the use of digital signatures some level of the communication protocol stack. Note that, in order to counter header swapping attacks, the signature SHOULD include both the SOAP body and any relevant SOAP headers (e.g. Sequence header). Because some headers (AckRequested, SequenceAcknowledgement) are independent of the body of the SOAP message in which they occur, implementations MUST allow for signatures that cover only these headers.

5.1.2 Resource Consumption Threats

The creation of a Sequence with an RM Destination consumes various resources on the systems used to implement that RM Destination. These resources can include network connections, database tables, message queues, etc. This behavior can be exploited to conduct denial of service attacks against an RM Destination. For example, a simple attack is to repeatedly send CreateSequence messages to an RM Destination. Another attack is to create a Sequence for a service that is known to require in-order message Delivery and use this Sequence to send a stream of very large messages to that service, making sure to omit message number “1” from that stream.

5.1.2.1 Countermeasures

There are a number of countermeasures against the described resource consumption threats. The technique advocated by this specification is for the RM Destination to restrict the ability to create a Sequence to a specific set of entities/principals. This reduces the number of potential attackers and, in some cases, allows the identity of any attackers to be determined.

The ability to restrict Sequence creation depends, in turn, upon the RM Destination's ability identify and authenticate the RM Source that issued the CreateSequence message.

5.1.3 Sequence Spoofing Threats

Sequence spoofing is a class of threats in which the attacker uses knowledge of the Identifier for a particular Sequence to forge Sequence Lifecycle or Traffic Messages. For example the attacker creates a fake TerminateSequence message that references the target Sequence and sends this message to the appropriate RM Destination. Some sequence spoofing attacks also require up-to-date knowledge of the current MessageNumber for their target Sequence.

In general any Sequence Lifecycle Message, RM Protocol Header Block, or sequence-correlated SOAP fault (e.g. InvalidAcknowledgement) can be used by someone with knowledge of the Sequence identifier to attack the Sequence. These attacks are “two-way” in that an attacker may choose to target the RM Source by, for example, inserting a fake SequenceAcknowledgement header into a message that it sends to the AcksTo EPR of an RM Source.

5.1.3.1 Sequence Hijacking

Sequence hijacking is a specific case of a sequence spoofing attack. The attacker attempts to inject Sequence Traffic Messages into an existing Sequence by inserting fake Sequence headers into those messages.

Note that “sequence hijacking” should not be equated with “security session hijacking”. Although a Sequence may be bound to some form of a security session in order to counter the threats described in this section, applications MUST NOT rely on WS-RM-related information to make determinations about the identity of the entity that created a message; applications SHOULD rely only upon information that is established by the security infrastructure to make such determinations. Failure to observe this rule creates, among other problems, a situation in which the absence of WS-RM may deprive an application of the ability to authenticate its peers even though the necessary security processing has taken place.

5.1.3.2 Countermeasures

There are a number of countermeasures against sequence spoofing threats. The technique advocated by this specification is to consider the Sequence to be a shared resource that is jointly owned by the RM Source that initiated its creation (i.e. that sent the CreateSequence message) and the RM Destination that serves as its terminus (i.e. that sent the CreateSequenceResponse message). To counter sequence spoofing attempts the RM Destination SHOULD ensure that every message or fault that it Receives that refers to a particular Sequence originated from the RM Source that jointly owns the referenced Sequence. For its part the RM Source SHOULD ensure that every message or fault that it Receives that refers to a particular Sequence originated from the RM Destination that jointly owns the referenced Sequence.

For the RM Destination to be able to identify its sequence peer it MUST be able to identify and authenticate the entity that sent the CreateSequence message. Similarly for the RM Source to identify its sequence peer it MUST be able to identify and authenticate the entity that sent the CreateSequenceResponse message. For either the RM Destination or the RM Source to determine if a message was sent by its sequence peer it MUST be able to identify and authenticate the initiator of that message and, if necessary, correlate this identity with the sequence peer identity established at sequence creation time.

5.2 Security Solutions and Technologies

The security threats described in the previous sections are neither new nor unique. The solutions that have been developed to secure other SOAP-based protocols can be used to secure WS-RM as well. This section maps the facilities provided by common web services security solutions against countermeasures described in the previous sections.

Before continuing this discussion, however, some examination of the underlying requirements of the previously described countermeasures is necessary. Specifically it should be noted that the technique described in Section 5.1.2.1 has two components. Firstly, the RM Destination identifies and authenticates the issuer of a CreateSequence message. Secondly, the RM Destination to performs an authorization check against this authenticated identity and determines if the RM Source is permitted to create Sequences with the RM Destination. Since the facilities for performing this authorization check (runtime infrastructure, policy frameworks, etc.) lie completely within the domain of individual implementations, any discussion of such facilities is considered to be beyond the scope of this specification.

5.2.1 Transport Layer Security

This section describes how the the facilities provided by SSL/TLS [RFC 4346] can be used to implement the countermeasures described in the previous sections. The use of SSL/TLS is subject to the constraints defined in Section 4 of the Basic Security Profile 1.0 [BSP 1.0].

The description provided here is general in nature and is not intended to serve as a complete definition on the use of SSL/TLS to protect WS-RM. In order to interoperate implementations need to agree on the choice of features as well as the manner in which they will be used. The mechanisms described in the Web Services Security Policy Language [SecurityPolicy] MAY be used by services to describe the requirements and constraints of the use of SSL/TLS.

5.2.1.1 Model

The basic model for using SSL/TLS is as follows:

  1. The RM Source establishes an SSL/TLS session with the RM Destination.

  2. The RM Source uses this SSL/TLS session to send a CreateSequence message to the RM Destination.

  3. The RM Destination establishes an SSL/TLS session with the RM Source and sends an asynchronous CreateSequenceResponse using this session. Alternately it may respond with a synchronous CreateSequenceResponse using the session established in (1).

  4. For the lifetime of the Sequence the RM Source uses the SSL/TLS session from (1) to Transmit any and all messages or faults that refer to that Sequence.

  5. For the lifetime of the Sequence the RM Destination either uses the SSL/TLS session established in (3) to Transmit any and all messages or faults that refer to that Sequence or, for synchronous exchanges, the RM Destination uses the SSL/TLS session established in (1).

5.2.1.2 Countermeasure Implementation

Used in its simplest fashion (without relying upon any authentication mechanisms), SSL/TLS provides the necessary integrity qualities to counter the threats described in Section 5.1.1. Note, however, that the nature of SSL/TLS limits the scope of this integrity protection to a single transport level session. If SSL/TLS is the only mechanism used to provide integrity, any intermediaries between the RM Source and the RM Destination MUST be trusted to preserve the integrity of the messages that flow through them.

As noted, the technique described in Sections 5.1.2.1 involves the use of authentication. This specification advocates either of two mechanisms for authenticating entities using SSL/TLS. In both of these methods the SSL/TLS server (the party accepting the SSL/TLS connection) authenticates itself to the SSL/TLS client using an X.509 certificate that is exchanged during the SSL/TLS handshake.

To implement the countermeasures described in section 5.1.2.1 the RM Source must authenticate itself using one the above mechanisms. The authenticated identity can then be used to determine if the RM Source is authorized to create a Sequence with the RM Destination.

This specification advocates implementing the countermeasures described in section 5.1.3.2 by requiring an RM node's Sequence peer to be equivalent to their SSL/TLS session peer. This allows the authorization decisions described in section 5.1.3.2 to be based on SSL/TLS session identity rather than on authentication information. For example, an RM Destination can determine that a Sequence Traffic Message rightfully belongs to its referenced Sequence if that message arrived over the same SSL/TLS session that was used to carry the CreateSequence message for that Sequence. Note that requiring a one-to-one relationship between SSL/TLS session peer and Sequence peer constrains the lifetime of a SSL/TLS-protected Sequence to be less than or equal to the lifetime of the SSL/TLS session that is used to protect that Sequence.

This specification does not preclude the use of other methods of using SSL/TLS to implement the countermeasures (such as associating specific authentication information with a Sequence) although such methods are not covered by this document.

Issues specific to the life-cycle management of SSL/TLS sessions (such as the resumption of a SSL/TLS session) are outside the scope of this specification.

5.2.2 SOAP Message Security

The mechanisms described in WS-Security may be used in various ways to implement the countermeasures described in the previous sections. This specification advocates using the protocol described by WS-SecureConversation [SecureConversation] (optionally in conjunction with WS-Trust [Trust]) as a mechanism for protecting Sequences. The use of WS-Security (as an underlying component of WS-SecureConversation) is subject to the constraints defined in the Basic Security Profile 1.0.

The description provided here is general in nature and is not intended to serve as a complete definition on the use of WS-SecureConversation/WS-Trust to protect WS-RM. In order to interoperate implementations need to agree on the choice of features as well as the manner in which they will be used. The mechanisms described in the Web Services Security Policy Language MAY be used by services to describe the requirements and constraints of the use of WS-SecureConversation.

5.2.2.1 Model

The basic model for using WS-SecureConversation is as follows:

  1. The RM Source and the RM Destination create a WS-SecureConversation security context. This may involve the participation of third parties such as a security token service. The tokens exchanged may contain authentication claims (e.g. X.509 certificates or Kerberos service tickets).

  2. During the CreateSequence exchange, the RM Source SHOULD explicitly identify the security context that will be used to protect the Sequence. This is done so that, in cases where the CreateSequence message is signed by more than one security context, the RM Source can indicate which security context should be used to protect the newly created Sequence.

  3. For the lifetime of the Sequence the RM Source and the RM Destination use the session key(s) associated with the security context to sign (as defined by WS-Security) at least the body and any relevant WS-RM-defined headers of any and all messages or faults that refer to that Sequence.

5.2.2.2 Countermeasure Implementation

Without relying upon any authentication information, the per-message signatures provide the necessary integrity qualities to counter the threats described in Section 5.1.1.

To implement the countermeasures described in section 5.1.2.1 some mutually agreed upon form of authentication claims must be provided by the RM Source to the RM Destination during the establishment of the Security Context. These claims can then be used to determine if the RM Source is authorized to create a Sequence with the RM Destination.

This specification advocates implementing the countermeasures described in section 5.1.3.2 by requiring an RM node's Sequence peer to be equivalent to their security context session peer. This allows the authorization decisions described in section 5.1.3.2 to be based on the identity of the message's security context rather than on any authentication claims that may have been established during security context initiation. Note that other methods of using WS-SecurityConversation to implement the countermeasures (such as associating specific authentication claims to a Sequence) are possible but not covered by this document.

As with transport security, the requisite equivalence of a security context peer and with a Sequence peer limits the lifetime of a Sequence to the lifetime of the protecting security context. Unlike transport security, the association between a Sequence and its protecting security context cannot always be established implicitly at Sequence creation time. This is due to the fact that the CreateSequence and CreateSequenceResponse messages may be signed by more than one security context.

Issues specific to the life-cycle management of WS-SecurityConversation security contexts (such as amending or renewing contexts) are outside the scope of this specification.

6 Securing Sequences

As noted in Section 5, the RM Source and RM Destination should be able to protect their shared Sequences against the threat of Sequence Spoofing attacks. There are a number of OPTIONAL means of achieving this objective depending upon the underlying security infrastructure.

6.1 Securing Sequences Using WS-Security

One mechanism for protecting a Sequence is to include a security token using a wsse:SecurityTokenReference element from WS-Security (see section 9 in WS-SecureConversation) in the CreateSequence element. This establishes an association between the created (and, if present, offered) Sequence(s) and the referenced security token, such that the RM Source and Destination MUST use the security token as the basis for authorization of all subsequent interactions related to the Sequence(s). The wsse:SecurityTokenReference explicitly identifies the token as there may be more than one token on a CreateSequence message or inferred from the communication context (e.g. transport protection).

It is RECOMMENDED that a message independent referencing mechanism be used to identify the token, if the token being referenced supports such mechanism.

The following exemplar defines the CreateSequence syntax when extended to include a wsse:SecurityTokenReference:

<wsrm:CreateSequence ...>
    <wsrm:AcksTo> wsa:EndpointReferenceType </wsrm:AcksTo>
    <wsrm:Expires ...> xs:duration </wsrm:Expires> ?
    <wsrm:Offer ...>
        <wsrm:Identifier ...> xs:anyURI </wsrm:Identifier>
        <wsrm:Endpoint> wsa:EndpointReferenceType </wsrm:Endpoint>
        <wsrm:Expires ...> xs:duration </wsrm:Expires> ?
        <wsrm:IncompleteSequenceBehavior>
            wsrm:IncompleteSequenceBehaviorType
        </wsrm:IncompleteSequenceBehavior> ?
        ...
    </wsrm:Offer> ?
    ...
    <wsse:SecurityTokenReference> 
      ... 
    </wsse:SecurityTokenReference> ? 
    ...
</wsrm:CreateSequence>
/wsrm:CreateSequence/wsse:SecurityTokenReference

This element uses the extensibility mechanism defined for the CreateSequence element (defined in section 3.1) to communicate an explicit reference to the security token, using a wsse:SecurityTokenReference as documented in WS-Security, that the RM Source and Destination MUST use to authorize messages for the created (and, if present, the offered) Sequence(s). All subsequent messages related to the created (and, if present, the offered) Sequence(s) MUST demonstrate proof-of-possession of the secret associated with the token (e.g., by using or deriving from a private or secret key).

When a RM Source Transmits a CreateSequence that has been extended to include a wsse:SecurityTokenReference it SHOULD ensure that the RM Destination both understands and will conform with the requirements listed above. In order to achieve this, the RM Source SHOULD include the UsesSequenceSTR element as a SOAP header block within the CreateSequence message. This element MUST include a soap:mustUnderstand attribute with a value of ‘true’. Thus the RM Source can be assured that a RM Destination that responds with a CreateSequenceResponse understands and conforms with the requirements listed above. Note that an RM Destination understanding this header does not mean that it has processed and understood any WS-Security headers, the fault behavior defined in WS-Security still applies.

The following exemplar defines the UsesSequenceSTR syntax:

<wsrm:UsesSequenceSTR ... />
/wsrm:UsesSequenceSTR

This element SHOULD be included as a SOAP header block in CreateSequence messages that use the extensibility mechanism described above in this section. The soap:mustUnderstand attribute value MUST be ‘true’. The receiving RM Destination MUST understand and correctly implement the extension described above or else generate a soap:MustUnderstand fault, thus aborting the requested Sequence creation.

The following is an example of a CreateSequence message using the wsse:SecurityTokenReference extension and the UsesSequenceSTR header block:

<soap:Envelope ...>
  <soap:Header>
    ...
    <wsrm:UsesSequenceSTR soap:mustUnderstand="true"/>
    ...
  </soap:Header>
  <soap:Body>
    <wsrm:CreateSequence>
      <wsrm:AcksTo>
        <wsa:Address>http://Business456.com/serviceA/789</wsa:Address>
      </wsrm:AcksTo>
      <wsse:SecurityTokenReference>
        ...
      </wsse:SecurityTokenReference>
    </wsrm:CreateSequence>
  </soap:Body>
</soap:Envelope>

6.2 Securing Sequences Using SSL/TLS

One mechanism for protecting a Sequence is to bind the Sequence to the underlying SSL/TLS session(s). The RM Source indicates to the RM Destination that a Sequence is to be bound to the underlying SSL/TLS session(s) via the UsesSequenceSSL header block. If the RM Source wishes to bind a Sequence to the underlying SSL/TLS sessions(s) it MUST include the UsesSequenceSSL element as a SOAP header block within the CreateSequence message.

The following exemplar defines the UsesSequenceSSL syntax:

<wsrm:UsesSequenceSSL soap:mustUnderstand="true" ... />
/wsrm:UsesSequenceSSL

The RM Source MAY include this element as a SOAP header block of a CreateSequence message to indicate to the RM Destination that the resulting Sequence is to be bound to the SSL/TLS session that was used to carry the CreateSequence message. If included, the RM Source MUST mark this header with a soap:mustUnderstand attribute with a value of ‘true’. The receiving RM Destination MUST understand and correctly implement the functionality described in Section 5.2.1 or else generate a soap:MustUnderstand fault, thus aborting the requested Sequence creation.

Note that the use inclusion of the above header by the RM Source implies that all Sequence-related information (Sequence Lifecycle or Acknowledgment messages or Sequence-related faults) flowing from the RM Destination to the RM Source will be bound to the SSL/TLS session that is used to carry the CreateSequenceResponse message.

7 References

7.1 Normative

[KEYWORDS]

S. Bradner, "Key words for use in RFCs to Indicate Requirement Levels," RFC 2119, Harvard University, March 1997

[SOAP 1.1]

W3C Note, "SOAP: Simple Object Access Protocol 1.1," 08 May 2000.

[SOAP 1.2]

W3C Recommendation, "SOAP Version 1.2 Part 1: Messaging Framework" June 2003.

[URI]

T. Berners-Lee, R. Fielding, L. Masinter, "Uniform Resource Identifiers (URI): Generic Syntax," RFC 3986, MIT/LCS, U.C. Irvine, Xerox Corporation, January 2005.

[UUID]

P. Leach, M. Mealling, R. Salz, "A Universally Unique IDentifier (UUID) URN Namespace," RFC 4122, Microsoft, Refactored Networks - LLC, DataPower Technology Inc, July 2005

[XML]

W3C Recommendation, "Extensible Markup Language (XML) 1.0 (Second Edition)", October 2000.

[XML-ns]

W3C Recommendation, "Namespaces in XML," 14 January 1999.

[XML-Schema Part1]

W3C Recommendation, "XML Schema Part 1: Structures," 2 May 2001.

[XML-Schema Part2]

W3C Recommendation, "XML Schema Part 2: Datatypes," 2 May 2001.

[XPATH 1.0]

W3C Recommendation, "XML Path Language (XPath) Version 1.0," 16 November 1999.

[WSDL 1.1]

W3C Note, "Web Services Description Language (WSDL 1.1)," 15 March 2001.

[WS-Addressing]

W3C Recommendation, “Web Services Addressing 1.0 - Core”, May 2006.

W3C Recommendation, “Web Services Addressing 1.0 – SOAP Binding”, May 2006.

7.2 Non-Normative

[BSP 1.0]

WS-I Working Group Draft. "Basic Security Profile Version 1.0," March 2006

[RDDL 2.0]

Johnathan Borden, Tim Bray, eds. “Resource Directory Description Language (RDDL) 2.0,” January 2004

[RFC 2617]

J. Franks, P. Hallam-Baker, J. Hostetler, S. Lawrence, P. Leach, A. Loutonen, L. Stewart, "HTTP Authentication: Basic and Digest Access Authentication," June 1999.

[RFC 4346]

T. Dierks, E. Rescorla, "The Transport Layer Security (TLS) Protocol Version 1.1," April 2006.

[WS-Policy]

W3C Member Submission, "Web Services Policy Framework (WS-Policy)," April 2006.

[WS-PolicyAttachment]

W3C Member Submission, "Web Services Policy Attachment (WS-PolicyAttachment)," April 2006.

[WS-Security]

Anthony Nadalin, Chris Kaler, Phillip Hallam-Baker, Ronald Monzillo, eds. "OASIS Web Services Security: SOAP Message Security 1.0 (WS-Security 2004)", OASIS Standard 200401, March 2004.

Anthony Nadalin, Chris Kaler, Phillip Hallam-Baker, Ronald Monzillo, eds. "OASIS Web Services Security: SOAP Message Security 1.1 (WS-Security 2004)", OASIS Standard 200602, February 2006.

[RTTM]

V. Jacobson, R. Braden, D. Borman,"TCP Extensions for High Performance", RFC 1323, May 1992.

[SecurityPolicy]

G. Della-Libra, et. al. "Web Services Security Policy Language (WS-SecurityPolicy)", July 2005

[SecureConversation]

S. Anderson, et al, "Web Services Secure Conversation Language (WS-SecureConversation)," February 2005.

[Trust]

S. Anderson, et al, "Web Services Trust Language (WS-Trust)," February 2005.

Appendix A. Schema

The normative schema that is defined for WS-ReliableMessaging using [XML-Schema Part1] and [XML-Schema Part2] is located at:

http://docs.oasis-open.org/ws-rx/wsrm/200608/wsrm-1.1-schema-200608.xsd

The following copy is provided for reference.

<?xml version="1.0" encoding="UTF-8"?>
<!-- 
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Copyright © OASIS Open 2002-2006. All Rights Reserved.
This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it or assist in its implementation may be prepared, copied, published and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. However, this document itself does not be modified in any way, such as by removing the copyright notice or references to OASIS, except as needed for the purpose of developing OASIS specifications, in which case the procedures for copyrights defined in the OASIS Intellectual Property Rights document must be followed, or as required to translate it into languages other than English.
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This document and the information contained herein is provided on an "AS IS" basis and OASIS DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
-->
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:wsa="http://www.w3.org/2005/08/addressing" xmlns:wsrm="http://docs.oasis-open.org/ws-rx/wsrm/200608" targetNamespace="http://docs.oasis-open.org/ws-rx/wsrm/200608" elementFormDefault="qualified" attributeFormDefault="unqualified">
  <xs:import namespace="http://www.w3.org/2005/08/addressing" schemaLocation="http://www.w3.org/2006/03/addressing/ws-addr.xsd"/>
  <!-- Protocol Elements -->
  <xs:complexType name="SequenceType">
    <xs:sequence>
      <xs:element ref="wsrm:Identifier"/>
      <xs:element name="MessageNumber" type="wsrm:MessageNumberType"/>
      <xs:any namespace="##other" processContents="lax" minOccurs="0" maxOccurs="unbounded"/>
    </xs:sequence>
    <xs:anyAttribute namespace="##other" processContents="lax"/>
  </xs:complexType>
  <xs:element name="Sequence" type="wsrm:SequenceType"/>
  <xs:element name="SequenceAcknowledgement">
    <xs:complexType>
      <xs:sequence>
        <xs:element ref="wsrm:Identifier"/>
        <xs:choice>
          <xs:sequence>
            <xs:choice>
              <xs:element name="AcknowledgementRange" maxOccurs="unbounded">
                <xs:complexType>
                  <xs:sequence/>
                  <xs:attribute name="Upper" type="xs:unsignedLong" use="required"/>
                  <xs:attribute name="Lower" type="xs:unsignedLong" use="required"/>
                  <xs:anyAttribute namespace="##other" processContents="lax"/>
                </xs:complexType>
              </xs:element>
              <xs:element name="None">
                <xs:complexType>
                  <xs:sequence/>
                </xs:complexType>
              </xs:element>
            </xs:choice>
            <xs:element name="Final" minOccurs="0">
              <xs:complexType>
                <xs:sequence/>
              </xs:complexType>
            </xs:element>
          </xs:sequence>
          <xs:element name="Nack" type="xs:unsignedLong" maxOccurs="unbounded"/>
        </xs:choice>
        <xs:any namespace="##other" processContents="lax" minOccurs="0" maxOccurs="unbounded"/>
      </xs:sequence>
      <xs:anyAttribute namespace="##other" processContents="lax"/>
    </xs:complexType>
  </xs:element>
  <xs:complexType name="AckRequestedType">
    <xs:sequence>
      <xs:element ref="wsrm:Identifier"/>
      <xs:any namespace="##other" processContents="lax" minOccurs="0" maxOccurs="unbounded"/>
    </xs:sequence>
    <xs:anyAttribute namespace="##other" processContents="lax"/>
  </xs:complexType>
  <xs:element name="AckRequested" type="wsrm:AckRequestedType"/>
  <xs:complexType name="MessagePendingType">
    <xs:sequence>
      <xs:any namespace="##other" processContents="lax" minOccurs="0" maxOccurs="unbounded"/>
    </xs:sequence>
    <xs:attribute name="pending" type="xs:boolean"/>
    <xs:anyAttribute namespace="##other" processContents="lax"/>
  </xs:complexType>
  <xs:element name="MessagePending" type="wsrm:MessagePendingType"/>
  <xs:element name="Identifier">
    <xs:complexType>
      <xs:annotation>
        <xs:documentation>
          This type is for elements whose [children] is an anyURI and can have arbitrary attributes.
        </xs:documentation>
      </xs:annotation>
      <xs:simpleContent>
        <xs:extension base="xs:anyURI">
          <xs:anyAttribute namespace="##other" processContents="lax"/>
        </xs:extension>
      </xs:simpleContent>
    </xs:complexType>
  </xs:element>
  <xs:element name="Address">
    <xs:complexType>
      <xs:simpleContent>
        <xs:extension base="xs:anyURI">
          <xs:anyAttribute namespace="##other" processContents="lax"/>
        </xs:extension>
      </xs:simpleContent>
    </xs:complexType>
  </xs:element>
  <xs:complexType name="MakeConnectionType">
    <xs:sequence>
      <xs:element ref="wsrm:Identifier" minOccurs="0" maxOccurs="1"/>
      <xs:element ref="wsrm:Address" minOccurs="0" maxOccurs="1"/>
      <xs:any namespace="##other" processContents="lax" minOccurs="0" maxOccurs="unbounded"/>
    </xs:sequence>
    <xs:anyAttribute namespace="##other" processContents="lax"/>
  </xs:complexType>
  <xs:element name="MakeConnection" type="wsrm:MakeConnectionType"/>
  <xs:simpleType name="MessageNumberType">
    <xs:restriction base="xs:unsignedLong">
      <xs:minInclusive value="1"/>
      <xs:maxInclusive value="9223372036854775807"/>
    </xs:restriction>
  </xs:simpleType>
  <!-- Fault Container and Codes -->
  <xs:simpleType name="FaultCodes">
    <xs:restriction base="xs:QName">
      <xs:enumeration value="wsrm:SequenceTerminated"/>
      <xs:enumeration value="wsrm:UnknownSequence"/>
      <xs:enumeration value="wsrm:InvalidAcknowledgement"/>
      <xs:enumeration value="wsrm:MessageNumberRollover"/>
      <xs:enumeration value="wsrm:CreateSequenceRefused"/>
      <xs:enumeration value="wsrm:SequenceClosed"/>
      <xs:enumeration value="wsrm:WSRMRequired"/>
      <xs:enumeration value="wsrm:UnsupportedSelection"/>
    </xs:restriction>
  </xs:simpleType>
  <xs:complexType name="SequenceFaultType">
    <xs:sequence>
      <xs:element name="FaultCode" type="wsrm:FaultCodes"/>
      <xs:element name="Detail" type="wsrm:DetailType" minOccurs="0"/>
      <xs:any namespace="##other" processContents="lax" minOccurs="0" maxOccurs="unbounded"/>
    </xs:sequence>
    <xs:anyAttribute namespace="##other" processContents="lax"/>
  </xs:complexType>
  <xs:complexType name="DetailType">
    <xs:sequence>
      <xs:any namespace="##other" processContents="lax" minOccurs="0" maxOccurs="unbounded"/>
    </xs:sequence>
    <xs:anyAttribute namespace="##other" processContents="lax"/>
  </xs:complexType>
  <xs:element name="SequenceFault" type="wsrm:SequenceFaultType"/>
  <xs:element name="CreateSequence" type="wsrm:CreateSequenceType"/>
  <xs:element name="CreateSequenceResponse" type="wsrm:CreateSequenceResponseType"/>
  <xs:element name="CloseSequence" type="wsrm:CloseSequenceType"/>
  <xs:element name="CloseSequenceResponse" type="wsrm:CloseSequenceResponseType"/>
  <xs:element name="TerminateSequence" type="wsrm:TerminateSequenceType"/>
  <xs:element name="TerminateSequenceResponse" type="wsrm:TerminateSequenceResponseType"/>
  <xs:complexType name="CreateSequenceType">
    <xs:sequence>
      <xs:element ref="wsrm:AcksTo"/>
      <xs:element ref="wsrm:Expires" minOccurs="0"/>
      <xs:element name="Offer" type="wsrm:OfferType" minOccurs="0"/>
      <xs:any namespace="##other" processContents="lax" minOccurs="0" maxOccurs="unbounded">
        <xs:annotation>
          <xs:documentation>
            It is the authors intent that this extensibility be used to transfer a Security Token Reference as defined in WS-Security.
          </xs:documentation>
        </xs:annotation>
      </xs:any>
    </xs:sequence>
    <xs:anyAttribute namespace="##other" processContents="lax"/>
  </xs:complexType>
  <xs:complexType name="CreateSequenceResponseType">
    <xs:sequence>
      <xs:element ref="wsrm:Identifier"/>
      <xs:element ref="wsrm:Expires" minOccurs="0"/>
      <xs:element name="IncompleteSequenceBehavior" type="wsrm:IncompleteSequenceBehaviorType" minOccurs="0"/>
      <xs:element name="Accept" type="wsrm:AcceptType" minOccurs="0"/>
      <xs:any namespace="##other" processContents="lax" minOccurs="0" maxOccurs="unbounded"/>
    </xs:sequence>
    <xs:anyAttribute namespace="##other" processContents="lax"/>
  </xs:complexType>
  <xs:complexType name="CloseSequenceType">
    <xs:sequence>
      <xs:element ref="wsrm:Identifier"/>
      <xs:any namespace="##other" processContents="lax" minOccurs="0" maxOccurs="unbounded"/>
    </xs:sequence>
    <xs:anyAttribute namespace="##other" processContents="lax"/>
  </xs:complexType>
  <xs:complexType name="CloseSequenceResponseType">
    <xs:sequence>
      <xs:element ref="wsrm:Identifier"/>
      <xs:any namespace="##other" processContents="lax" minOccurs="0" maxOccurs="unbounded"/>
    </xs:sequence>
    <xs:anyAttribute namespace="##other" processContents="lax"/>
  </xs:complexType>
  <xs:complexType name="TerminateSequenceType">
    <xs:sequence>
      <xs:element ref="wsrm:Identifier"/>
      <xs:any namespace="##other" processContents="lax" minOccurs="0" maxOccurs="unbounded"/>
    </xs:sequence>
    <xs:anyAttribute namespace="##other" processContents="lax"/>
  </xs:complexType>
  <xs:complexType name="TerminateSequenceResponseType">
    <xs:sequence>
      <xs:element ref="wsrm:Identifier"/>
      <xs:any namespace="##other" processContents="lax" minOccurs="0" maxOccurs="unbounded"/>
    </xs:sequence>
    <xs:anyAttribute namespace="##other" processContents="lax"/>
  </xs:complexType>
  <xs:element name="AcksTo" type="wsa:EndpointReferenceType"/>
  <xs:complexType name="OfferType">
    <xs:sequence>
      <xs:element ref="wsrm:Identifier"/>
      <xs:element name="Endpoint" type="wsa:EndpointReferenceType"/>
      <xs:element ref="wsrm:Expires" minOccurs="0"/>
      <xs:element name="IncompleteSequenceBehavior" type="wsrm:IncompleteSequenceBehaviorType" minOccurs="0"/>
      <xs:any namespace="##other" processContents="lax" minOccurs="0" maxOccurs="unbounded"/>
    </xs:sequence>
    <xs:anyAttribute namespace="##other" processContents="lax"/>
  </xs:complexType>
  <xs:complexType name="AcceptType">
    <xs:sequence>
      <xs:element ref="wsrm:AcksTo"/>
      <xs:any namespace="##other" processContents="lax" minOccurs="0" maxOccurs="unbounded"/>
    </xs:sequence>
    <xs:anyAttribute namespace="##other" processContents="lax"/>
  </xs:complexType>
  <xs:element name="Expires">
    <xs:complexType>
      <xs:simpleContent>
        <xs:extension base="xs:duration">
          <xs:anyAttribute namespace="##other" processContents="lax"/>
        </xs:extension>
      </xs:simpleContent>
    </xs:complexType>
  </xs:element>
  <xs:simpleType name="IncompleteSequenceBehaviorType">
    <xs:restriction base="xs:string">
      <xs:enumeration value="DiscardEntireSequence"/>
      <xs:enumeration value="DiscardFollowingFirstGap"/>
      <xs:enumeration value="NoDiscard"/>
    </xs:restriction>
  </xs:simpleType>
  <xs:element name="UsesSequenceSTR">
    <xs:sequence/>
    <xs:anyAttribute namespace="##other" processContents="lax"/>
  </xs:element>
  <xs:element name="UsesSequenceSSL">
    <xs:sequence/>
    <xs:anyAttribute namespace="##other" processContents="lax"/>
  </xs:element>
  <xs:element name="UnsupportedElement">
    <xs:simpleType>
      <xs:restriction base="xs:QName"/>
    </xs:simpleType>
  </xs:element>
</xs:schema>

Appendix B. WSDL

The normative WSDL 1.1 definition for WS-ReliableMessaging is located at:

http://docs.oasis-open.org/ws-rx/wsrm/200608/wsdl/wsrm-1.1-wsdl-200608.wsdl

The following non-normative copy is provided for reference.

<?xml version="1.0" encoding="utf-8"?>
<!-- 
OASIS takes no position regarding the validity or scope of any intellectual property or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; neither does it represent that it has made any effort to identify any such rights. Information on OASIS's procedures with respect to rights in OASIS specifications can be found at the OASIS website. Copies of claims of rights made available for publication and any assurances of licenses to be made available, or the result of an attempt made to obtain a general license or permission for the use of such proprietary rights by implementors or users of this specification, can be obtained from the OASIS Executive Director.
OASIS invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights which may cover technology that may be required to implement this specification. Please address the information to the OASIS Executive Director.
Copyright (c) OASIS Open 2002-2006. All Rights Reserved.
This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it or assist in its implementation may be prepared, copied, published and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. However, this document itself does not be modified in any way, such as by removing the copyright notice or references to OASIS, except as needed for the purpose of developing OASIS specifications, in which case the procedures for copyrights defined in the OASIS Intellectual Property Rights document must be followed, or as required to translate it into languages other than English.
The limited permissions granted above are perpetual and will not be revoked by OASIS or its successors or assigns.
This document and the information contained herein is provided on an "AS IS" basis and OASIS DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
-->
<wsdl:definitions xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:wsa="http://www.w3.org/2005/08/addressing" xmlns:rm="http://docs.oasis-open.org/ws-rx/wsrm/200608" xmlns:tns="http://docs.oasis-open.org/ws-rx/wsrm/200608/wsdl" targetNamespace="http://docs.oasis-open.org/ws-rx/wsrm/200608/wsdl">

  <wsdl:types>
    <xs:schema>
      <xs:import namespace="http://docs.oasis-open.org/ws-rx/wsrm/200608" schemaLocation="http://docs.oasis-open.org/ws-rx/wsrm/200608/wsrm-1.1-schema-200608.xsd"/>
    </xs:schema>
  </wsdl:types>

  <wsdl:message name="CreateSequence">
    <wsdl:part name="create" element="rm:CreateSequence"/>
  </wsdl:message>
  <wsdl:message name="CreateSequenceResponse">
    <wsdl:part name="createResponse" element="rm:CreateSequenceResponse"/>
  </wsdl:message>
  <wsdl:message name="CloseSequence">
    <wsdl:part name="close" element="rm:CloseSequence"/>
  </wsdl:message>
  <wsdl:message name="CloseSequenceResponse">
    <wsdl:part name="closeResponse" element="rm:CloseSequenceResponse"/>
  </wsdl:message>
  <wsdl:message name="TerminateSequence">
    <wsdl:part name="terminate" element="rm:TerminateSequence"/>
  </wsdl:message>
  <wsdl:message name="TerminateSequenceResponse">
    <wsdl:part name="terminateResponse" element="rm:TerminateSequenceResponse"/>
  </wsdl:message>
  <wsdl:message name="MakeConnection">
    <wsdl:part name="makeConnection" element="rm:MakeConnection"/>
  </wsdl:message>

  <wsdl:portType name="SequenceAbstractPortType">
    <wsdl:operation name="CreateSequence">
      <wsdl:input message="tns:CreateSequence" wsa:Action="http://docs.oasis-open.org/ws-rx/wsrm/200608/CreateSequence"/>
      <wsdl:output message="tns:CreateSequenceResponse" wsa:Action="http://docs.oasis-open.org/ws-rx/wsrm/200608/CreateSequenceResponse"/>
    </wsdl:operation>
    <wsdl:operation name="CloseSequence">
      <wsdl:input message="tns:CloseSequence" wsa:Action="http://docs.oasis-open.org/ws-rx/wsrm/200608/CloseSequence"/>
      <wsdl:output message="tns:CloseSequenceResponse" wsa:Action="http://docs.oasis-open.org/ws-rx/wsrm/200608/CloseSequenceResponse"/>
    </wsdl:operation>
    <wsdl:operation name="TerminateSequence">
      <wsdl:input message="tns:TerminateSequence" wsa:Action="http://docs.oasis-open.org/ws-rx/wsrm/200608/TerminateSequence"/>
      <wsdl:output message="tns:TerminateSequenceResponse" wsa:Action="http://docs.oasis-open.org/ws-rx/wsrm/200608/TerminateSequenceResponse"/>
    </wsdl:operation>
    <wsdl:operation name="MakeConnection">
      <wsdl:input message="tns:MakeConnection" wsa:Action="http://docs.oasis-open.org/ws-rx/wsrm/200608/MakeConnection"/>
    </wsdl:operation>
  </wsdl:portType>

</wsdl:definitions>

Appendix C. Message Examples

Appendix C.1 Create Sequence

Create Sequence

<?xml version="1.0" encoding="UTF-8"?>
<S:Envelope xmlns:S="http://www.w3.org/2003/05/soap-envelope" 
xmlns:wsrm="http://docs.oasis-open.org/ws-rx/wsrm/200608" 
xmlns:wsa="http://www.w3.org/2005/08/addressing">
 <S:Header>
  <wsa:MessageID>
   http://Business456.com/guid/0baaf88d-483b-4ecf-a6d8-a7c2eb546817
  </wsa:MessageID>
  <wsa:To>http://example.com/serviceB/123</wsa:To>
    <wsa:Action>http://docs.oasis-open.org/ws-rx/wsrm/200608/CreateSequence</wsa:Action>
  <wsa:ReplyTo>
   <wsa:Address>http://Business456.com/serviceA/789</wsa:Address>
  </wsa:ReplyTo>
 </S:Header>
 <S:Body>
  <wsrm:CreateSequence>
    <wsrm:AcksTo>
      <wsa:Address>http://Business456.com/serviceA/789</wsa:Address>
    </wsrm:AcksTo>
  </wsrm:CreateSequence>
 </S:Body>
</S:Envelope>

Create Sequence Response

<?xml version="1.0" encoding="UTF-8"?>
<S:Envelope xmlns:S="http://www.w3.org/2003/05/soap-envelope" xmlns:wsrm="http://docs.oasis-open.org/ws-rx/wsrm/200608" xmlns:wsa="http://www.w3.org/2005/08/addressing">
  <S:Header>
    <wsa:To>http://Business456.com/serviceA/789</wsa:To>
    <wsa:RelatesTo>
      http://Business456.com/guid/0baaf88d-483b-4ecf-a6d8a7c2eb546817
    </wsa:RelatesTo>
    <wsa:Action>
      http://docs.oasis-open.org/ws-rx/wsrm/200608/CreateSequenceResponse
    </wsa:Action>
  </S:Header>
  <S:Body>
    <wsrm:CreateSequenceResponse>
      <wsrm:Identifier>http://Business456.com/RM/ABC</wsrm:Identifier>
    </wsrm:CreateSequenceResponse>
  </S:Body>
</S:Envelope>

Appendix C.2 Initial Transmission

The following example WS-ReliableMessaging headers illustrate the message exchange in the above figure. The three messages have the following headers; the third message is identified as the last message in the Sequence:

Message 1

<?xml version="1.0" encoding="UTF-8"?>
<S:Envelope xmlns:S="http://www.w3.org/2003/05/soap-envelope"
xmlns:wsrm="http://docs.oasis-open.org/ws-rx/wsrm/200608"
xmlns:wsa="http://www.w3.org/2005/08/addressing">
  <S:Header>
    <wsa:MessageID>
      http://Business456.com/guid/71e0654e-5ce8-477b-bb9d-34f05cfcbc9e
    </wsa:MessageID>
    <wsa:To>http://example.com/serviceB/123</wsa:To>
    <wsa:From>
      <wsa:Address>http://Business456.com/serviceA/789</wsa:Address>
    </wsa:From>
    <wsa:Action>http://example.com/serviceB/123/request</wsa:Action>
    <wsrm:Sequence>
      <wsrm:Identifier>http://Business456.com/RM/ABC</wsrm:Identifier>
      <wsrm:MessageNumber>1</wsrm:MessageNumber>
    </wsrm:Sequence>
  </S:Header>
  <S:Body>
    <!--  Some  Application  Data  -->
  </S:Body>
</S:Envelope>

Message 2

<?xml version="1.0" encoding="UTF-8"?>
<S:Envelope xmlns:S="http://www.w3.org/2003/05/soap-envelope" 
xmlns:wsrm="http://docs.oasis-open.org/ws-rx/wsrm/200608" 
xmlns:wsa="http://www.w3.org/2005/08/addressing">
  <S:Header>
    <wsa:MessageID>
      http://Business456.com/guid/daa7d0b2-c8e0-476e-a9a4-d164154e38de
    </wsa:MessageID>
    <wsa:To>http://example.com/serviceB/123</wsa:To>
    <wsa:From>
      <wsa:Address>http://Business456.com/serviceA/789</wsa:Address>
    </wsa:From>
    <wsa:Action>http://example.com/serviceB/123/request</wsa:Action>
    <wsrm:Sequence>
      <wsrm:Identifier>http://Business456.com/RM/ABC</wsrm:Identifier>
      <wsrm:MessageNumber>2</wsrm:MessageNumber>
    </wsrm:Sequence>
  </S:Header>
  <S:Body>
    <!--  Some  Application  Data  -->
  </S:Body>
</S:Envelope>

Message 3

<?xml version="1.0" encoding="UTF-8"?>
<S:Envelope xmlns:S="http://www.w3.org/2003/05/soap-envelope" 
xmlns:wsrm="http://docs.oasis-open.org/ws-rx/wsrm/200608" 
xmlns:wsa="http://www.w3.org/2005/08/addressing">
 <S:Header>
  <wsa:MessageID>
   http://Business456.com/guid/0baaf88d-483b-4ecf-a6d8-a7c2eb546819
  </wsa:MessageID>
  <wsa:To>http://example.com/serviceB/123</wsa:To>
  <wsa:From>
   <wsa:Address>http://Business456.com/serviceA/789</wsa:Address>
  </wsa:From>
  <wsa:Action>http://example.com/serviceB/123/request</wsa:Action>
  <wsrm:Sequence>
   <wsrm:Identifier>http://Business456.com/RM/ABC</wsrm:Identifier>
   <wsrm:MessageNumber>3</wsrm:MessageNumber>
  </wsrm:Sequence>
  <wsrm:AckRequested>
    <wsrm:Identifier>http://Business456.com/RM/ABC</wsrm:Identifier>
  </wsrm:AckRequested>
 </S:Header>
 <S:Body>
  <!-- Some Application Data -->
 </S:Body>
</S:Envelope>

Appendix C.3 First Acknowledgement

Message number 2 has not been accepted by the RM Destination due to some transmission error so it responds with an Acknowledgement for messages 1 and 3:

<?xml version="1.0" encoding="UTF-8"?>
<S:Envelope xmlns:S="http://www.w3.org/2003/05/soap-envelope" 
xmlns:wsrm="http://docs.oasis-open.org/ws-rx/wsrm/200608" 
xmlns:wsa="http://www.w3.org/2005/08/addressing">
 <S:Header>
  <wsa:MessageID>
   http://example.com/guid/0baaf88d-483b-4ecf-a6d8-a7c2eb546810
  </wsa:MessageID>
  <wsa:To>http://Business456.com/serviceA/789</wsa:To>
  <wsa:From>
   <wsa:Address>http://example.com/serviceB/123</wsa:Address>
  </wsa:From>
  <wsa:Action>
    http://docs.oasis-open.org/ws-rx/wsrm/200608/SequenceAcknowledgement
  </wsa:Action>
  <wsrm:SequenceAcknowledgement>
   <wsrm:Identifier>http://Business456.com/RM/ABC</wsrm:Identifier>
   <wsrm:AcknowledgementRange Upper="1" Lower="1"/>
   <wsrm:AcknowledgementRange Upper="3" Lower="3"/>
  </wsrm:SequenceAcknowledgement>
 </S:Header>
 <S:Body/>
</S:Envelope>

Appendix C.4 Retransmission

The RM Source discovers that message number 2 was not accepted so it resends the message and requests an Acknowledgement:

<?xml version="1.0" encoding="UTF-8"?>
<S:Envelope xmlns:S="http://www.w3.org/2003/05/soap-envelope" 
xmlns:wsrm="http://docs.oasis-open.org/ws-rx/wsrm/200608" 
xmlns:wsa="http://www.w3.org/2005/08/addressing">
 <S:Header>
  <wsa:MessageID>
   http://Business456.com/guid/daa7d0b2-c8e0-476e-a9a4-d164154e38de
  </wsa:MessageID>
  <wsa:To>http://example.com/serviceB/123</wsa:To>
  <wsa:From>
   <wsa:Address>http://Business456.com/serviceA/789</wsa:Address>
  </wsa:From>
  <wsa:Action>http://example.com/serviceB/123/request</wsa:Action>
  <wsrm:Sequence>
   <wsrm:Identifier>http://Business456.com/RM/ABC</wsrm:Identifier>
   <wsrm:MessageNumber>2</wsrm:MessageNumber>
  </wsrm:Sequence>
  <wsrm:AckRequested>
   <wsrm:Identifier>http://Business456.com/RM/ABC</wsrm:Identifier>
  </wsrm:AckRequested>
 </S:Header>
 <S:Body>
  <!-- Some Application Data -->
 </S:Body>
</S:Envelope>

Appendix C.5 Termination

The RM Destination now responds with an Acknowledgement for the complete Sequence which can then be terminated:

<?xml version="1.0" encoding="UTF-8"?>
<S:Envelope xmlns:S="http://www.w3.org/2003/05/soap-envelope"
xmlns:wsrm="http://docs.oasis-open.org/ws-rx/wsrm/200608" 
xmlns:wsa="http://www.w3.org/2005/08/addressing">
 <S:Header>
  <wsa:MessageID>
   http://example.com/guid/0baaf88d-483b-4ecf-a6d8-a7c2eb546811
  </wsa:MessageID>
  <wsa:To>http://Business456.com/serviceA/789</wsa:To>
  <wsa:From>
   <wsa:Address>http://example.com/serviceB/123</wsa:Address>
  </wsa:From>
  <wsa:Action>
    http://docs.oasis-open.org/ws-rx/wsrm/200608/SequenceAcknowledgement
  </wsa:Action>
  <wsrm:SequenceAcknowledgement>
   <wsrm:Identifier>http://Business456.com/RM/ABC</wsrm:Identifier>
   <wsrm:AcknowledgementRange Upper="3" Lower="1"/>
  </wsrm:SequenceAcknowledgement>
 </S:Header>
 <S:Body/>
</S:Envelope>

Terminate Sequence

<?xml version="1.0" encoding="UTF-8"?>
<S:Envelope xmlns:S="http://www.w3.org/2003/05/soap-envelope" 
xmlns:wsrm="http://docs.oasis-open.org/ws-rx/wsrm/200608" 
xmlns:wsa="http://www.w3.org/2005/08/addressing">
 <S:Header>
  <wsa:MessageID>
   http://Business456.com/guid/0baaf88d-483b-4ecf-a6d8-a7c2eb546812
  </wsa:MessageID>
  <wsa:To>http://example.com/serviceB/123</wsa:To>
  <wsa:Action>
    http://docs.oasis-open.org/ws-rx/wsrm/200608/TerminateSequence
  </wsa:Action>
  <wsa:From>
   <wsa:Address>http://Business456.com/serviceA/789</wsa:Address>
  </wsa:From>
 </S:Header>
 <S:Body>
  <wsrm:TerminateSequence>
   <wsrm:Identifier>http://Business456.com/RM/ABC</wsrm:Identifier>
  </wsrm:TerminateSequence>
 </S:Body>
</S:Envelope>

Terminate Sequence Response

<?xml version="1.0" encoding="UTF-8"?>
<S:Envelope xmlns:S="http://www.w3.org/2003/05/soap-envelope" 
xmlns:wsrm="http://docs.oasis-open.org/ws-rx/wsrm/200608" 
xmlns:wsa="http://www.w3.org/2005/08/addressing">
 <S:Header>
  <wsa:MessageID>
   http://Business456.com/guid/0baaf88d-483b-4ecf-a6d8-a7c2eb546813
  </wsa:MessageID>
  <wsa:To>http://example.com/serviceA/789</wsa:To>
  <wsa:Action>
    http://docs.oasis-open.org/ws-rx/wsrm/200608/TerminateSequenceResponse
  </wsa:Action>
  <wsa:RelatesTo>
    http://Business456.com/guid/0baaf88d-483b-4ecf-a6d8-a7c2eb546812
  </wsa:RelatesTo>
  <wsa:From>
   <wsa:Address>http://Business456.com/serviceA/789</wsa:Address>
  </wsa:From>
 </S:Header>
 <S:Body>
  <wsrm:TerminateSequenceResponse>
   <wsrm:Identifier>http://Business456.com/RM/ABC</wsrm:Identifier>
  </wsrm:TerminateSequenceResponse>
 </S:Body>
</S:Envelope>

Appendix C.6 MakeConnection

To illustrate how a MakeConnection message exchange can be used to deliver messages to an Endpoint that is not addressable, consider the case of a pub/sub scenario in which the Endpoint to which notifications are to be delivered (the "event consumer") is not addressable by the notification sending Endpoint (the "event producer"). In this scenario the event consumer must initiate the connections in order for the notifications to be delivered. One possible set of message exchanges (using HTTP) that demonstrate how this can be achieved using MakeConnection is shown below.

Step 1 – During a "subscribe" operation, the event consumer's EPR specifies the RM anonymous URI and the RM Policy Assertion to indicate whether or not RM is required:

<S:Envelope xmlns:S="http://www.w3.org/2003/05/soap-envelope" 
xmlns:wsrm="http://docs.oasis-open.org/ws-rx/wsrm/200608"
xmlns:wsrmp="http://docs.oasis-open.org/ws-rx/wsrmp/200608"
xmlns:wsa="http://www.w3.org/2005/08/addressing">
  <S:Header>
    <wsa:To> http://example.org/subscriptionService </wsa:To>
    <wsa:MessageID> http://client456.org/id-a6d8-a7c2eb546813</wsa:MessageID>
    <wsa:ReplyTo>
      <wsa:To> http://client456.org/response </wsa:To>
    </wsa:ReplyTo>
  </S:Header>
  <S:Body>
    <sub:Subscribe xmlns:sub="http://exaaple.org/subscriptionService">
      <!-- subscription service specific data -->
      <targetEPR>
        <wsa:Address>http://docs.oasis-open.org/ws-rx/wsrm/200608/anonymous?id=550e8400-e29b-11d4-a716-446655440000</wsa:Address>
        <wsa:Metadata>
          <wsp:Policy wsu:Id="MyPolicy">
            <wsrmp:RMAssertion/>
          </wsp:Policy>
        </wsa:Metadata>
      </targetEPR>
    </sub:Subscribe>
  </S:Body>
</S:Envelope>

In this example the subscribe and targetEPR elements are simply examples of what a subscription request message might contain. Note: the wsa:Address element contains the RM anonymous URI indicating that the notification producer needs to queue the messages until they are requested using the MakeConnection message exchange. The EPR also contains the RM Policy Assertion indicating the RM must be used when notifications related to this subscription are sent.

Step 2 – Once the subscription is established, the event consumer checks for a pending message:

<S:Envelope xmlns:S="http://www.w3.org/2003/05/soap-envelope" 
xmlns:wsrm="http://docs.oasis-open.org/ws-rx/wsrm/200608" 
xmlns:wsa="http://www.w3.org/2005/08/addressing">
  <S:Header>
    <wsa:Action>http://docs.oasis-open.org/ws-rx/wsrm/200608/MakeConnection</wsa:Action>
    <wsa:To> http://example.org/subscriptionService </wsa:To>
  </S:Header>
  <S:Body>
    <wsrm:MakeConnection>
      <wsrm:Address>http://docs.oasis-open.org/ws-rx/wsrm/200608/anonymous?id=550e8400-e29b-11d4-a716-446655440000</wsrm:Address>
    </wsrm:MakeConnection>
  </S:Body>
</S:Envelope>

Step 3 – If there are messages waiting to be delivered then a message will be returned back to the event consumer. However, because WS-RM is being used to deliver the messages, the first message returned is a CreateSequence:

<S:Envelope xmlns:S="http://www.w3.org/2003/05/soap-envelope" 
xmlns:wsrm="http://docs.oasis-open.org/ws-rx/wsrm/200608" 
xmlns:wsa="http://www.w3.org/2005/08/addressing">
  <S:Header>
    <wsa:Action>http://docs.oasis-open-org/ws-rx/wsrm/200608/CreateSequence</wsa:Action>
    <wsa:To>http://docs.oasis-open.org/ws-rx/wsrm/200608/anonymous?id=550e8400-e29b-11d4-a716-446655440000</wsa:To>
    <wsa:ReplyTo> http://example.org/subscriptionService </wsa:ReplyTo>
    <wsa:MessageID> http://example.org/id-123-456 </wsa:MessagID>
  </S:Header>
  <S:Body>
    <wsrm:CreateSequence>
      <wsrm:AcksTo>
        <wsa:Address> http://example.org/subscriptionService </wsa:Address>
      </wsrm:AcksTo>
    </wsrm:CreateSequence>
  </S:Body>
</S:Envelope>

Notice from the perspective of how the RM Source on the event producer interacts with the RM Destination of those messages, nothing new is introduced by the use of the MakeConnection, the use of RM protocol is the same as the case where the event consumer is addressable.

Step 4 – The event consumer will respond with a CreateSequenceResponse message per normal WS-Addressing rules:

<S:Envelope xmlns:S="http://www.w3.org/2003/05/soap-envelope" 
xmlns:wsrm="http://docs.oasis-open.org/ws-rx/wsrm/200608" 
xmlns:wsa="http://www.w3.org/2005/08/addressing">
  <S:Header>
    <wsa:Action>http://docs.oasis-open-org/ws-rx/wsrm/200608/CreateSequenceResponse</wsa:Action>
    <wsa:To> http://example.org/subscriptionService </wsa:To>
    <wsa:RelatesTo> http://example.org/id-123-456 </wsa:RelatesTo>
  </S:Header>
  <S:Body>
    <wsrm:CreateSequenceResponse>
      <wsrm:Identifier> http://example.org/rmid-456 </wsrm:Identifier>
    </wsrm:CreateSequenceResponse>
  </S:Body>
</S:Envelope>

Note, this message is carried on an HTTP request directed to the wsa:ReplyTo EPR, and the HTTP response will be an HTTP 202.

Step 5 – The event consumer checks for another message pending:

<S:Envelope xmlns:S="http://www.w3.org/2003/05/soap-envelope" 
xmlns:wsrm="http://docs.oasis-open.org/ws-rx/wsrm/200608" 
xmlns:wsa="http://www.w3.org/2005/08/addressing">
  <S:Header>
    <wsa:Action>http://docs.oasis-open.org/ws-rx/wsrm/200608/MakeConnection</wsa:Action>
    <wsa:To> http://example.org/subscriptionService </wsa:To>
  </S:Header>
  <S:Body>
    <wsrm:MakeConnection>
      <wsrm:Address>http://docs.oasis-open.org/ws-rx/wsrm/200608/anonymous?id=550e8400-e29b-11d4-a716-446655440000</wsrm:Address>
    </wsrm:MakeConnection>
  </S:Body>
</S:Envelope>

Notice this is the same message as the one sent in step 2.

Step 6 – If there is a message pending for this destination then it is returned on the HTTP response:

<S:Envelope xmlns:S="http://www.w3.org/2003/05/soap-envelope" 
xmlns:wsrm="http://docs.oasis-open.org/ws-rx/wsrm/200608" 
xmlns:wsa="http://www.w3.org/2005/08/addressing">
  <S:Header>
    <wsa:Action> http://example.org/eventType1 </wsa:Action>
    <wsa:To>http://docs.oasis-open.org/ws-rx/wsrm/200608/anonymous?id=550e8400-e29b-11d4-a716-446655440000</wsa:To>
    <wsrm:Sequence>
      <wsrm:Identifier> http://example.org/rmid-456 </wsrm:Identifier>
    </wsrm:Sequence>
    <wsrm:MessagePending pending="true"/>
  </S:Header>
  <S:Body>
    <!-- event specific data -->
  </S:Body>
</S:Envelope>

As noted in step 3, the use of the RM protocol does not change when using MakeConnection. The format of the messages, the order of the messages sent and the timing of when to send it remains the same.

Step 7 – At some later interval, or immediately due to the MessagePending header's "pending" attribute being set to "true", the event consumer will poll again:

<S:Envelope xmlns:S="http://www.w3.org/2003/05/soap-envelope" 
xmlns:wsrm="http://docs.oasis-open.org/ws-rx/wsrm/200608" 
xmlns:wsa="http://www.w3.org/2005/08/addressing">
  <S:Header>
    <wsa:Action>http://docs.oasis-open.org/ws-rx/wsrm/200608/MakeConnection</wsa:Action>
    <wsa:To> http://example.org/subscriptionService </wsa:To>
  </S:Header>
  <S:Body>
    <wsrm:MakeConnection>
      <wsrm:Address>http://docs.oasis-open.org/ws-rx/wsrm/200608/anonymous?id=550e8400-e29b-11d4-a716-446655440000</wsrm:Address>
    </wsrm:MakeConnection>
  </S:Body>
</S:Envelope>

Notice this is the same message as the one sent in steps 2 and 5. As in steps 3 and 6, the response to the MakeConnection can be any message destined to the specified Endpoint. This allows the event producer to send not only application messages but RM protocol messages (e.g. CloseSequence, TerminateSequence or even additional CreateSequences) as needed.

Step 8 – If at any point in time there are no messages pending, in response to a MakeConnection the event producer returns an HTTP 202 back to the event consumer. The process then repeats (back to step 7) until the subscription ends.

Appendix D. State Tables

This appendix specifies the non-normative state transition tables for RM Source and RM Destination.

The state tables describe the lifetime of a sequence in both the RM Source and the RM Destination

Legend:

The first column of these tables contains the motivating event and has the following format:

Event

Event name
[source]

{ref}

Where:

Each event / state combination cell in the tables in this appendix has the following format:

State Name

Action to take
[next state]

{ref}

Where:

N/A” in a cell indicates a state / event combination self-inconsistent with the state machine; should these conditions occur, it would indicate an implementation error. A blank cell indicates that the behavior is not described in this specification and does not indicate normal protocol operation. Implementations MAY generate a Sequence Terminated fault (see section 4.2) in these circumstances. Robust implementations MUST be able to operate in a stable manner despite the occurrence of unspecified event / state combinations.

Table 1 RM Source Sequence State Transition Table

Events

Sequence States

None

Creating

Created

Closing

Closed

Terminating

Create Sequence
[unspec]
{3.1}

Xmit Create Sequence
[Creating]
{3.1}

N/A

N/A

N/A

N/A

N/A

Create Sequence Response
[msg]
{3.1)

 

Process Create Sequence Response
[Created]
{3.1}

 

 

 

 

Create Sequence Refused Fault
[msg]
{3.1}

 

No action
[None]
{4.6}

 

 

 

 

Send message
[app]
{2.1}

N/A

N/A

Xmit message

[Same]
{2}

No action

[Same]
{2}

N/A

N/A

Retransmit of un-ack’d message
[int]

N/A

N/A

Xmit message

[Same]
{2.4}

Xmit message

[Same]
{2.4}

N/A

N/A

SeqAck (non-final)
[msg]
{3.6}

Generate Unknown Sequence Fault
[Same]
{4.3}

Generate Unknown Sequence Fault
[Same]
{4.3}

Process Ack ranges

[Same]
{3.6}

Process Ack ranges

[Same]
{3.6}

Process Ack ranges

[Same]
{3.6}

Process Ack ranges

[Same]
{3.6}

Nack
[msg]
{3.6)

Generate Unknown Sequence Fault
[Same]
{4.3}

Generate Unknown Sequence Fault
[Same]
{4.3}

<Xmit message(s)>
[Same]
{3.6}

<Xmit message(s)>
[Same]
{3.6}

No action

[Same]

No action

[Same]

Message Number Rollover Fault
[msg]

Generate Unknown Sequence Fault
[Same]
{4.3}

Generate Unknown Sequence Fault
[Same]
{4.3}

No action

[Rollover]

No action

[Same]

No action

[Same]

No action

[Same]

<Close Sequence>
[int]
{3.2}

N/A

 

Xmit Close Sequence
[Closing]
{3.2}

N/A

N/A

N/A

Close Sequence Response
[msg]
{3.2}

Generate Unknown Sequence Fault
[Same]
{4.3}

Generate Unknown Sequence Fault
[Same]
{4.3}

 

No action

[Closed]
{3.2}

No action

[Same]
{3.2}

No action

[Same]
{3.2}

SeqAck (final)
[msg]
{3.6}

Generate Unknown Sequence Fault
[Same]
{4.3}

Generate Unknown Sequence Fault
[Same]
{4.3}

Process Ack ranges
[Closed]
{3.6}

Process Ack ranges
[Closed]
{3.6}

Process Ack ranges
[Same]

Process Ack ranges
[Same]

Sequence Closed Fault
[msg]
{4.7}

Generate Unknown Sequence Fault
[Same]
{4.3}

Generate Unknown Sequence Fault
[Same]
{4.3}

No action
[Closed]
{4.7}

No action
[Closed]
{4.7}

No action
[Same]

No action
[Same]

Unknown Sequence Fault
[msg]
{4.3}

 

 

Terminate Sequence
[None]
{4.3}

Terminate Sequence
[None]
{4.3}

Terminate Sequence
[None]
{4.3}

Terminate Sequence
[None]
{4.3}

Sequence Terminated Fault
[msg]
{4.2}

N/A

 

Terminate Sequence
[None]
{4.2}

Terminate Sequence
[None]
{4.2}

Terminate Sequence
[None]
{4.2}

Terminate Sequence
[None]
{4.2}

Terminate Sequence
[int]

N/A

No action
[None]
{unspec}

Xmit Terminate Sequence
[Terminating]

Xmit Terminate Sequence
[Terminating]

Xmit Terminate Sequence
[Terminating]

N/A

Terminate Sequence Response
[msg]

Generate Unknown Sequence Fault
[Same]
{4.3}

Generate Unknown Sequence Fault
[Same]
{4.3}

 

 

 

Terminate
Sequence
[None]
{3.3}

Expires exceeded
[int]

N/A

Terminate Sequence
[None]
{3.4}

Terminate Sequence
[None]
{3.4}

Terminate Sequence
[None]
{3.4}

Terminate Sequence
[None]
{3.4}

Terminate Sequence
[None]
{3.4}

Invalid Acknowledgement
[msg]
{4.4]

Generate Unknown Sequence Fault
[Same]
{4.3}

Generate Unknown Sequence Fault
[Same]
{4.3}

Generate Invalid Acknowledgement Fault
[Same]
{4.4}

Generate Invalid Acknowledgement Fault
[Same]
{4.4}

Generate Invalid Acknowledgement Fault
[Same]
{4.4}

Generate Invalid Acknowledgement Fault
[Same]
{4.4}



Table 2 RM Destination Sequence State Transition Table

Events

Sequence States

None

Created

Closed

CreateSequence
(successful)
[msg/int]
{3.1}

Xmit Create Sequence Response
[Created]
{3.1}

N/A

N/A

CreateSequence
(unsuccessful)
[msg/int]
{3.1}

Generate Create Sequence Refused Fault
[None]
{3.1}

N/A

N/A

Message (with message number within range)
[msg]

Generate Unknown Sequence Fault
[Same]
{4.3}

Accept Message;
<Xmit SeqAck>
[Same]

Generate Sequence Closed Fault (with SeqAck+Final)
[Same]
{3.2}

Message (with message number outside of range)
[msg]

Generate Unknown Sequence Fault
[Same]
{4.3}

Xmit Message Number Rollover Fault
[Same]
{3.4}{4.5}

Generate Sequence Closed Fault (with SeqAck+Final)
[Same]
{3.2}

<AckRequested>
[msg]
{3.5}

Generate Unknown Seq Fault
[Same]
{4.3}

Xmit SeqAck
[Same]
{3.5}

Xmit SeqAck+Final
[Same]
{3.6}

CloseSequence
[msg]
{3.2}

Generate Unknown Sequence Fault
[Same]
{4.3}

Xmit CloseSequence Response with SeqAck+Final
[Closed]
{3.2}

Generate Sequence Closed Fault
[Same]
{4.7}

<CloseSequence autonomously>
[int]

N/A

No Action
[Closed]

N/A

TerminateSequence
[msg]
{3.3)

Generate Unknown Sequence Fault
[Same]
{4.3}

Xmit Terminate Sequence Response
[None]
{3.3}

Xmit Terminate Sequence Response
[None]
{3.3}

UnknownSequence Fault
[msg]
{4.3}

 

Terminate Sequence
[None]
{4.3}

Terminate Sequence
[None]
{4.3}

SequenceTerminated Fault
[msg]
{4.2}

 

Terminate Sequence
[None]
{4.2}

Terminate Sequence
[None]
{4.2}

Invalid Acknowledgement Fault
[msg]
{4.4}

N/A

 

 

Expires exceeded
[int]

N/A

Terminate Sequence
[None]
{3.4}

Terminate Sequence
[None]
{3.4}

<Seq Acknowledgement autonomously>
[int]
{3.6}

N/A

Xmit SeqAck
[Same]
{3.6}

Xmit SeqAck+Final
[Same]
{3.6}

Non WSRM message when WSRM required
[msg]
{4.8}

Generate WSRMRequired Fault
[Same]
{4.8}

Generate WSRMRequired Fault
[Same]
{4.8}

Generate WSRMRequired Fault
[Same]
{4.8}



The following two tables apply only if the MakeConnection mechanism is utilized.

Table 3 Sending Endpoint Message Transfer Engine

Event

None

Queued n=1

Queued, n>1

Message destined to anon Endpoint when channel unavailable
[int]
{3.7}

Queue message
[Queued n=1]

Queue message
[Queued n>1]

Queue message
[Queued n>1]

MakeConnection
[msg]
{3.7}

 

Send message
[none]

Xmit message with MessagePending
[if n=2 then (Queued n=1) else (Queued n>1)]



Table 4 Receiving Endpoint Message Transfer Engine

Event

None

Polling

Expectation of unreceived message
[int, unspecified]

No Action
[Polling]

No Action
[Same]

Polling trigger
[int, unspecified]

 

Xmit MakeConnection
[Polling]
(3.7}



Appendix E. Acknowledgments

This document is based on initial contribution to OASIS WS-RX Technical Committee by the following authors:

Ruslan Bilorusets(BEA), Don Box(Microsoft), Luis Felipe Cabrera(Microsoft), Doug Davis(IBM), Donald Ferguson(IBM), Christopher Ferris-Editor(BM), Tom Freund(IBM), Mary Ann Hondo(IBM), John Ibbotson(IBM), Lei Jin(BEA), Chris Kaler(Microsoft), David Langworthy-Editor(Microsoft), Amelia Lewis(TIBCO Software), Rodney Limprecht(Microsoft), Steve Lucco(Microsoft), Don Mullen(TIBCO Software), Anthony Nadalin(IBM), Mark Nottingham(BEA), David Orchard(BEA), Jamie Roots(IBM), Shivajee Samdarshi(TIBCO Software), John Shewchuk(Microsoft), Tony Storey(IBM).

The following individuals have provided invaluable input into the initial contribution:

Keith Ballinger(Microsoft), Stefan Batres(Microsoft), Rebecca Bergersen(Iona), Allen Brown(Microsoft), Michael Conner(IBM), George Copeland(Microsoft), Francisco Curbera(IBM), Paul Fremantle(IBM), Steve Graham(IBM), Pat Helland(Microsoft), Rick Hill(Microsoft), Scott Hinkelman(IBM), Tim Holloway(IBM), Efim Hudis(Microsoft), David Ingham(Microsoft), Gopal Kakivaya(Microsoft), Johannes Klein(Microsoft), Frank Leymann(IBM), Martin Nally(IBM), Peter Niblett(IBM), Jeffrey Schlimmer(Microsoft), James Snell(IBM), Keith Stobie(Microsoft), Satish Thatte(Microsoft), Stephen Todd(IBM), Sanjiva Weerawarana(IBM), Roger Wolter(Microsoft).

The following individuals were members of the committee during the development of this specification:

Abbie Barbir(Nortel), Charlton Barreto(Adobe), Stefan Batres(Microsoft), Hamid Ben Malek(Fujitsu), Andreas Bjarlestam(Ericsson), Toufic Boubez(Layer 7), Doug Bunting(Sun), Lloyd Burch(Novell), Steve Carter(Novell), Martin Chapman(Oracle), Dave Chappell(Sonic), Paul Cotton(Microsoft), Glen Daniels(Sonic), Doug Davis(IBM), Blake Dournaee(Intel), Jacques Durand(Fujitsu), Colleen Evans(Microsoft), Christopher Ferris(IBM), Paul Fremantle(WSO2), Robert Freund(Hitachi), Peter Furniss(Erebor), Marc Goodner(Microsoft), Alastair Green(Choreology), Mike Grogan(Sun), Ondrej Hrebicek(Microsoft), Kazunori Iwasa(Fujitsu), Chamikara Jayalath(WSO2), Lei Jin(BEA), Ian Jones(BTplc), Anish Karmarkar(Oracle), Paul Knight(Nortel), Dan Leshchiner(Tibco), Mark Little(JBoss), Lily Liu(webMethods), Matt Lovett(IBM), Ashok Malhotra(Oracle), Jonathan Marsh(Microsoft), Daniel Millwood(IBM), Jeff Mischkinsky(Oracle), Nilo Mitra(Ericsson), Peter Niblett(IBM), Duane Nickull(Adobe), Eisaku Nishiyama(Hitachi), Dave Orchard(BEA), Chouthri Palanisamy(NEC), Sanjay Patil(SAP), Gilbert Pilz(BEA), Martin Raepple(SAP), Eric Rajkovic(Oracle), Stefan Rossmanith(SAP), Tom Rutt(Fujitsu), Rich Salz(IBM), Shivajee Samdarshi(Tibco), Vladimir Videlov(SAP), Claus von Riegen(SAP), Pete Wenzel(Sun), Steve Winkler(SAP), Ümit Yalçinalp(SAP), Nobuyuki Yamamoto(Hitachi).

Appendix F. Revision History

Rev

Date

By Whom

What

wd-01

2005-07-07

Christopher Ferris

Initial version created based on submission by the authors.

ws-02

2005-07-21

Doug Davis

I011 (PT0S) added

wd-02

2005-08-16

Anish Karmarkar

Trivial editorial changes

ws-03

2005-09-15

Doug Davis

I019 and i028 (CloseSeq) added

wd-05

2005-09-26

Gilbert Pilz

i005 (Source resend of nacks messages when ack already received) added.

wd-05

2005-09-27

Doug Davis

i027 (InOrder delivery assurance spanning multiple sequences) added

wd-05

2005-09-27

Doug Davis

i020 (Semantics of “At most once” Delivery Assurance) added

wd-05

2005-09-27

Doug Davis

i034 (Fault while processing a piggy-backed RM header) added

wd-05

2005-09-27

Doug Davis

i033 (Processing model of NACKs) added

wd-05

2005-09-27

Doug Davis

i031 (AckRequested schema inconsistency) added

wd-05

2005-09-27

Doug Davis

i025 (SeqAck/None) added

wd-05

2005-09-27

Doug Davis

i029 (Remove dependency on WS-Security) added

wd-05

2005-09-27

Doug Davis

i039 (What does 'have a mU attribute' mean) added

wd-05

2005-09-27

Doug Davis

i040 (Change 'optiona'/'required' to 'OPTIONAL'/'REQUIRED') added

wd-05

2005-09-30

Anish Karmarkar

i017 (Change NS to http://docs.oasis-open.org/wsrm/200510/)

wd-05

2005-09-30

Anish Karmarkar

i045 (Include SecureConversation as a reference and move it to non-normative citation)

wd-05

2005-09-30

Anish Karmarkar

i046 (change the type of wsrm:FaultCode element)

wd-06

2005-11-02

Gilbert Pilz

Start wd-06 by changing title page from cd-01.

wd-06

2005-11-03

Gilbert Pilz

i047 (Reorder spec sections)

wd-07

2005-11-17

Gilbert Pilz

Start wd-07

wd-07

2005-11-28

Doug Davis

i071 – except for period in Appendix headings

wd-07

2005-11-28

Doug Davis

i10

wd-07

2005-11-28

Doug Davis

i030

wd-07

2005-11-28

Doug Davis

i037

wd-07

2005-11-28

Doug Davis

i038

wd-07

2005-11-28

Doug Davis

i041

wd-07

2005-11-28

Doug Davis

i043

wd-07

2005-11-28

Doug Davis

i044

wd-07

2005-11-28

Doug Davis

i048

wd-07

2005-11-28

Doug Davis

i051

wd-07

2005-11-28

Doug Davis

i053

wd-07

2005-11-28

Doug Davis

i059

wd-07

2005-11-28

Doug Davis

i062

wd-07

2005-11-28

Doug Davis

i063

wd-07

2005-11-28

Doug Davis

i065

wd-07

2005-11-28

Doug Davis

i067

wd-07

2005-11-28

Doug Davis

i068

wd-07

2005-11-28

Doug Davis

i069

wd-07

2005-11-28

Doug Davis

Fix bulleted list (#2) in section 2.3

wd-07

2005-11-29

Gilbert Pilz

i074 (Use of [tcShortName] in artifact locations namespaces, etc)

wd-07

2005-11-29

Gilbert Pilz

i071 – Fixed styles and formating for TOC. Fixed styles of the appendix headings.

wd-07

2005-11-30

Doug Davis

Removed dup definition of "Receive"

wd-07

2005-11-30

Gilbert Pilz

Fixed lost formatting from heading for Namespace section. Fixed style of text body elements to match OASIS example documents. Fixed tables to match OASIS example documents.

wd-07

2005-12-01

Gilbert Pilz

Updated fix for i074 to eliminate trailing '/'. Added corresponding text around action IRI composition.

wd-07

2005-12-01

Gilbert Pilz

Use non-fixed fields for date values on both title page and body footers.

wd-07

2005-12-01

Doug Davis

Alphabetize the glossary

wd-07

2005-12-02

Doug Davis

i064

wd-07

2005-12-02

Doug Davis

i066

wd-08

2005-12-15

Doug Davis

Add back in RM Source to glossary

wd-08

2005-12-15

Steve Winkler

Doug added Steve's editorial nits

wd-08

2005-12-21

Doug Davis

i050

wd-08

2005-12-21

Doug Davis

i081

wd-08

2005-12-21

Doug Davis

i080 – but i050 negates the need for any changes

wd-08

2005-12-21

Doug Davis

i079

wd-08

2005-12-21

Doug Davis

I076 – didn't add text about "replies" since the RMD to RMS sequence could be used for any message not just replies

wd-08

2005-12-21

Umit Yalcinalp

Action Su03: removed wsse from Table 1

wd-08

2005-12-21

Umit Yalcinalp

I057 per Sunnyvale F2F 2005, Cleaned up some formatting errors in contributors

wd-08

2005-12-27

Doug Davis

i060

wd-08

2005-12-27

Gilbert Pilz

Moved schema and WSDL files to their own artifacts. Converted source document to OpenDocument Text format. Changed line numbers to be a single style.

wd-08

2005-12-28

Anish Karmarkar

Included a section link to c:\temp\wsrm-1.1-schema-200510.xsd and to c:\temp\wsrm-1.1-wsdl-200510.wsdl

wd-08

2006-01-04

Gilbert Pilz

Fixed formatting for included sections.

wd-08

2006-01-05

Gilbert Pilz

Created links for unused references. Fixed exemplars for CloseSequence and CloseSequenceResponse.

wd-09

2006-01-11

Doug Davis

Minor tweaks to text/typos.

wd-10

2006-01-23

Doug Davis

Accept all changes from wd-09

Make some minor editoral tweaks from Marc's comments.

wd-10

2006-02-14

Doug Davis

Issue 082 resolution

wd-10

2006-02-14

Doug Davis

Issue 083 resolution

wd-10

2006-02-14

Doug Davis

Issue 085 resolution

wd-10

2006-02-14

Doug Davis

Issues 086, 087 resolutions

Defined MessageNumberType

wd-10

2006-02-15

Doug Davis

Issue 078 resolution

wd-10

2006-02-15

Doug Davis

Issue 094 resolution

wd-10

2006-02-15

Doug Davis

Issue 095 resolution

wd-10

2006-02-15

Gilbert Pilz

Issue 088 – added namespace URI link to namespace URI; added text explaining that this URI could be dereferenced to produce the RDDL doc; added non-normative reference to RDDL 2.0

wd-10

2006-02-17

Anish Karmarkar

Namespace changed to 200602 for both WSDL and XSD docs.

wd-10

2006-02-17

Anish Karmarkar

Issue i087 as it applies to WSRM spec.

wd-10

2006-02-17

Anish Karmarkar

Added titles and minor text for state table (issue i058).

wd-11

2006-02-22

Doug Davis

Accept all changes for new WD

Minor typos fixed

wd-11

2006-02-23

Doug Davis

s/'close'/close/g – per Marc Goodner

Added first ref to [URI] – per Marc G again

wd-11

2006-02-27

Doug Davis

Issue i061 applied

wd-11

2006-02-28

Doug Davis

Fixed typo around the use of "above" and "below"

wd-11

2006-03-01

Doug Davis

Minor typos found by Marc Goodner

wd-11

2006-03-02

Doug Davis

Minor typos found by Matt Lovett

wd-11

2006-03-08

Doug Davis

Issue 091 applied

wd-11

2006-03-08

Doug Davis

Issue 092 applied

wd-11

2006-03-08

Doug Davis

Issue 100 applied

wd-12

2006-03-20

Doug Davis

Added space in "SOAP1.x" – PaulCotton

wd-12

2006-04-11

Doug Davis

Issue 007 applied

wd-12

2006-04-11

Doug Davis

Issue 090 applied

wd-12

2006-04-11

Doug Davis

Issue 098 applied

wd-12

2006-04-11

Doug Davis

Issue 099 applied

wd-12

2006-04-11

Doug Davis

Issue 101 applied

wd-12

2006-04-11

Doug Davis

Issue 103 applied

wd-12

2006-04-11

Doug Davis

Issue 104 applied

wd-12

2006-04-11

Doug Davis

Issue 105 applied

wd-12

2006-04-11

Doug Davis

Issue 107 applied

wd-12

2006-04-11

Doug Davis

Issue 109 applied

wd-12

2006-04-11

Doug Davis

Issue 110 applied

wd-12

2006-04-12

Doug Davis

Used "generated" instead of "issue" or "send" when talking about faults.

wd-12

2006-04-24

Gilbert Pilz

Update references to WS-Addressing to the Proposed Recommendations; update WS-RM namespace to “200604”.

wd-13

2006-05-08

Gilbert Pilz

i093 part 1; more work needed

wd-13

2006-05-10

Doug Davis

Issue 096 applied

wd-13

2006-05-26

Gilbert Pilz

i093 part 2; reflects decisions from 2006-05-25 meeting

wd-13

2006-05-28

Gilbert Pilz

Issue 106 applied

wd-13

2006-05-29

Gilbert Pilz

Issue 118 applied

wd-13

2006-05-29

Gilbert Pilz

Issue 120 applied

wd-13

2006-05-30

Gilbert Pilz

Issue 114 applied

wd-13

2006-05-30

Gilbert Pilz

Issue 116 applied

wd-14

2006-06-05

Gilbert Pilz

Accept all changes; bump WD number

wd-14

2006-06-07

Doug Davis

Applied lots of minor edits from Marc Goodner

wd-14

2006-06-07

Doug Davis

Change a couple of period/sp/sp to period/sp

wd-14

2006-06-07

Doug Davis

Added a space in "URI])of" – per Marc Goodner

wd-14

2006-06-07

Doug Davis

Issue 131 applied

wd-14

2006-06-07

Doug Davis

Issue 132 applied

wd-14

2006-06-07

Doug Davis

Issue 119 applied

wd-14

2006-06-07

Doug Davis

Applied lots of minor edits from Doug Davis

wd-14

2006-06-07

Doug Davis

s/"none"/"full-uri"/ - per Marc Goodner

wd-14

2006-06-12

Doug Davis

Complete i106

wd-14

2006-06-12

Doug Davis

Issues 089 applied

wd-14

2006-06-12

Doug Davis

Fix for several RFC2119 keywords – per Anish

wd-15

2006-06-12

Doug Davis

Accept all changed, dump WD number

wd-15

2006-06-12

Doug Davis

Move WSDL after Schema

wd-15

2006-06-12

Doug Davis

Nits – remove tabs, extra [yyy]'s ...

wd-15

2006-06-14

Doug Davis

Remove extra "OPTIONAL"s – Matt Lovett

wd-15

2006-06-14

Doug Davis

Remove blank rows/columns from state table. Fix italics in state table

wd-15

2006-06-15

Doug Davis

Typo – section D was empty

wd-15

2006-06-16

Doug Davis

Issue 125 applied

wd-15

2006-06-16

Doug Davis

Issue 126 applied

wd-15

2006-06-16

Doug Davis

Issue 127 applied

wd-15

2006-06-16

Doug Davis

Issue 133 applied

wd-15

2006-06-16

Doug Davis

Issue 136 applied

wd-15

2006-06-16

Doug Davis

Issue 138 applied

wd-15

2006-06-16

Doug Davis

Issue 135 applied

wd-15

2006-06-20

Doug Davis

Added all TC members to the ack list

wd-15

2006-06-22

Doug Davis

Issue 129 applied

wd-15

2006-06-22

Doug Davis

Issue 130 applied

wd-15

2006-06-22

Doug Davis

Issue 137 applied

wd-15

2006-06-26

Doug Davis

Issue 111 applied

wd-15

2006-06-26

Doug Davis

Missed a part of issue 129

wd-15

2006-06-30

Doug Davis

Fixed a typo in schema

wd-15

2006-06-30

Doug Davis

Issue 141 applied

wd-15

2006-06-30

Doug Davis

Issue 142 applied

wd-15

2006-06-30

Doug Davis

Issue 148 applied

wd-15

2006-06-30

Doug Davis

Issue 149 applied

wd-15

2006-06-30

Doug Davis

Issue 150 applied

wd-15

2006-07-06

Doug Davis

Issue 121 applied

wd-15

2006-07-21

Doug Davis

Issue 139 applied

wd-15

2006-07-21

Doug Davis

Issue 144 applied

wd-15

2006-07-21

Doug Davis

Issue 147 applied

wd-15

2006-07-21

Doug Davis

Issues 122-124 applied

wd-15

2006-07-27

Doug Davis

Updated list of oasis TC members (i134)

wd-15

2006-07-27

Doug Davis

Issue 140 applied

wd-15

2006-07-27

Doug Davis

Issue 145 applied

wd-15

2006-07-27

Doug Davis

Issue 143 applied

wd-15

2006-07-28

Doug Davis

Lots of minor typos found by Matt L.

wd-15

2006-07-28

Doug Davis

Issue 113 applied

wd-15

2006-08-04

Doug Davis

Update old namespaces – found by PaulC

wd-15

2006-08-04

Doug Davis

Issue 150 applied

wd-15

2006-08-04

Doug Davis

Minor typos – found by PeterN

wd-15

2006-08-04

Doug Davis

Verify all [refs]

wd-15

2006-08-04

Doug Davis

Change namespace to 2006/08

wd-15

2006-08-04

Doug Davis

Issue 148 applied

wd-15

2006-08-07

Doug Davis

Add some new glossary terms – per GilP

cd-04

2006-08-10

Gilbert Pilz

Formatting changes for better HTML rendering.

cd-04

2006-08-11

Doug Davis

Issue 158 applied

cd-04

2006-08-11

Doug Davis

Issue 153 applied

cd-04

2006-08-11

Doug Davis

Issue 156 applied

cd-04

2006-08-15

Gilbert Pilz

More formatting changes for better HTML rendering.

Appendix G. Notices

OASIS takes no position regarding the validity or scope of any intellectual property or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; neither does it represent that it has made any effort to identify any such rights. Information on OASIS's procedures with respect to rights in OASIS specifications can be found at the OASIS website. Copies of claims of rights made available for publication and any assurances of licenses to be made available, or the result of an attempt made to obtain a general license or permission for the use of such proprietary rights by implementors or users of this specification, can be obtained from the OASIS Executive Director.

OASIS invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights which may cover technology that may be required to implement this specification. Please address the information to the OASIS Executive Director.

Copyright (C) OASIS Open (2006). All Rights Reserved.

This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it or assist in its implementation may be prepared, copied, published and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. However, this document itself may not be modified in any way, such as by removing the copyright notice or references to OASIS, except as needed for the purpose of developing OASIS specifications, in which case the procedures for copyrights defined in the OASIS Intellectual Property Rights document must be followed, or as required to translate it into languages other than English.

The limited permissions granted above are perpetual and will not be revoked by OASIS or its successors or assigns.

This document and the information contained herein is provided on an "AS IS" basis and OASIS DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.