OASIS Web Services Transaction Technical Committee

Call for Participation: OASIS Web Services Transaction Technical Committee

Date:      Sat, 01 Oct 2005 08:26:59 -0700
From:      James Bryce Clark <jamie.clark@oasis-open.org>
To:        members@lists.oasis-open.org,
           tc-announce@lists.oasis-open.org
Subject:   OASIS TC Call for Participation: OASIS Web Services Transaction Technical Committee

A new OASIS technical committee is being formed. The OASIS Web Services Transaction Technical Committee has been proposed by the members of OASIS listed below. The proposal (below) meets the requirements of the OASIS TC Process [1]. The TC name, statement of purpose, scope, list of deliverables, audience, and language specified in the proposal will constitute the TC's official charter. Submissions of technology for consideration by the TC, and the beginning of technical discussions, may occur no sooner than the TC's first meeting.

This TC will operate under our 2005 IPR Policy [2]. The eligibility requirements for becoming a participant in the TC at the first meeting (see details below) are that:

you must be an employee of an OASIS member organization or an individual member of OASIS
the OASIS member must sign the OASIS membership agreement (see [3])
you must notify the TC chair of your intent to participate at least 15 days prior to the first meeting, which members may do by using the "Join this TC" button on the TC's public page at [4] and
you must attend the first meeting of the TC, at the time and date fixed below.

Of course, it also will be possible to join the TC at a later time. Standards always are improved by broad participation.

Non-OASIS members who wish to participate may contact us about joining OASIS [3]. Our rules and structure are designed to promote inclusiveness. We look forward to assisting parties interested in joining the community of implementers, technologists, academics and end-users working on OASIS standardization projects. All also are welcome to take advantage of the public resources maintained for each TC: a mail list archive, document repository and public comments facility, which will be available via the TC's public home page at [4]. Archives of the TC's mail list and public comment lists, as with all OASIS TCs, will be visible at [5].

Further information generally related to the topic area addressed by this TC may be found on the Cover Pages at "Messaging and Transaction Coordination":

http://xml.coverpages.org/coordination.html

Please feel free to forward this announcement to any other appropriate lists. OASIS is an open standards organization; we encourage your feedback. JBC

James Bryce Clark
Director, Standards Development, OASIS
jamie.clark@oasis-open.org

[1] http://www.oasis-open.org/committees/process.php
[2] http://www.oasis-open.org/who/intellectualproperty.php
[3] See http://www.oasis-open.org/join/
[4] http://www.oasis-open.org/committees/tc_home.php?wg_abbrev=ws-tx
[5] http://lists.oasis-open.org/archives/

Charter: OASIS Web Services Transaction TC

Name of the TC

OASIS Web Services Transaction (WS-TX) Technical Committee

Statement of Purpose

The purpose of the Web Services Transaction (WS-TX) Technical Committee (TC) is to define a set of protocols to coordinate the outcomes of distributed application actions.

The TC will specify an extensible framework for developing coordination protocols through continued refinement of the Web Services Coordination (WS-Coordination v 1.0) [1] specification submitted to the TC as referenced in this charter.

In addition, the TC will continue refinement of protocols for two coordination types that use the WS-Coordination framework: atomic transaction (AT) and business activity (BA), based on the Web Services Atomic Transaction (WS-AtomicTransaction v 1.0) [2] and Web Services Business Activity (WS-BusinessActivity v 1.0) [3] specifications submitted to the TC.

Collectively, these three specifications will be referred to as the WS-TX Specifications.

This document assumes the reader has a basic knowledge of coordination protocols and current practice as it relates to atomic transaction management and long running activities. A familiarity with the concepts and terms may also be obtained through books such as "Transaction Processing: Concepts & Technologies" by Gray & Reuter [4], and "Principles of Transaction Processing" by Bernstein and Newcomer [5].

Scope of Work

The TC will accept as input version 1.0 of the WS-Coordination [1], WS-AT [2] and WS-BA [3] specifications (the Input Documents) as published by Arjuna Technologies, BEA Systems, Hitachi, IBM, IONA Technologies and Microsoft. Other contributions and changes to the input documents will be accepted for consideration without any prejudice or restrictions and evaluated based on technical merit in so far as they conform to this charter.

The scope of the TC's work is to continue further refinement and finalization of the input documents to produce as output modular specifications that standardize the concepts, WSDL documents and XML schema renderings required to coordinate actions of distributed applications that conform to the specifications.

The WS-TX TC shall produce three inter-related specifications:

A WS-Coordination v 1.1 specification providing protocols for services that create a coordination context, which uniquely identifies an activity, and register participants in the activity.
A WS-AtomicTransaction v 1.1 specification specifying concrete protocols for distributed atomic transactions using the well-known two-phase commit abstract protocol.
A WS-BusinessActivity v 1.1 specification providing a protocol for long-running activities using a compensation protocol.

As general principles, these protocols should:

Focus on ease of interoperation.
Use simple but complete state machines, preferring simplicity and completeness to elaboration.
Specify concrete protocol message formats.
Use message formats that include extensibility points for implementations to add custom elements as required within the context of message semantics and schemas.
Support the extensibility of coordination types for use in control protocols outside the scope of this TC.
Include state machines that specify the events and messages (including fault messages) that may be received at each different state in the protocol.
Must not depend on the availability of reliable message delivery mechanisms outside of these specifications.

The specifications will uphold the basic principles of other Web services specifications of independence and composition and must be composable with the other specifications in the Web services architecture such as WS-Security [6], WS-Trust [7], WS-SecureConversation [8], WS-Addressing [9], SOAP 1.1 [10], SOAP 1.2 [11], bindings of SOAP 1.1/1.2 to HTTP, WS-Policy [12], WSDL 1.1 [13] and WSDL 2.0 [14]. The "Secure, Reliable, Transacted Web Services: Architecture and Composition" white paper [15] published in 2003 provides information on the Web services architecture. The TC will also take into consideration applicable work, such as the WS-I Basic Profile [16].

If any above specification is outside of a standardization process at the time this TC moves to ratify its deliverables, or is not far enough along in the standardization process, any normative references to it in the TC output will be expressed in an abstract manner, and the incarnation will be left at that time as an exercise in interoperability.

While enabling composition with other specifications is a goal of the TC, it is also a goal to leave the specifics of how that composition is achieved outside the scope of the WS-TX specifications.

Each of the protocol elements will use implementation and language neutral message formats defined in WSDL [13] and XML formats defined in XML Schema [17]. SOAP [10, 11] bindings will be specified for the message protocol elements.

The scope of these three specifications is detailed below.

The WS-Coordination specification consists of:

The definition of a coordination service as an aggregate of an activation service, a registration service, a CoordinationContext XML type, and a set of specific coordination service protocols.
The definition of protocols for communicating with an activation service, that service having two purposes:
- Creating a coordination context for a new activity.
- Creating a coordination context for an existing activity into which the coordination service has been interposed.
The definition of protocols for communicating with a registration service, that service having the purpose of allowing a web service to register to participate in a specific coordination protocol relating to a specific activity.
The notion of a coordination type as an independent service, not defined in the WS-Coordination specification, which provides a set of coordination protocols.
The notion of a coordination protocol as an independent message exchange pattern, not defined in the WS-Coordination specification, which is associated with a coordination type.
A binding-specific mechanism for propagating coordination context elements representing activities between applications, including a SOAP-binding that uses the SOAP header of a SOAP message.
The definition of protocols for communicating with a registration service that can be used by an application to register itself into the overall activity.
A coordination context usable within a SOAP header that identifies the activity type, the activity identifier, the activity expiration time, an appropriate pre-registration service, and protocol specific extensions. The context can be used by other coordination protocols, including, but not limited to, those produced by this TC.

The coordination specification MUST be able to compose with WS-Security [6], WS-Trust [7], and WS-SecureConversation [8] to realize the following security goals in a simple and interoperable way:

Ensure that only authorized principals (see [15]) can create or register with a coordination context
Verify that a coordination context is legitimate and has not suffered from tampering
Allow composition with existing and federated security infrastructures
Limit the transaction participation to authorized participants and applications

The coordination specification must also provide a mechanism that restricts registration on an activity to those applications to whom the right to register was delegated from the root coordinator. This mechanism must associate a security token with each coordination context. The WS-Trust <IssuedTokens> element must be used to flow security tokens in SOAP message headers alongside coordination contexts.

The WS-AtomicTransaction specification consists of:

Definition of a coordination type suitable for coordination in a two-phase commit protocol
Definition of a completion protocol which can be used by a service to signal the initiation of commitment processing and to receive notification of the success or failure of the subsequent two-phase commitment
Durable and Volatile variants of a two-phase commit (2PC) protocol
Policy assertions qualifying instances of protocol usage

The volatile resource and the durable resource variations of the two-phase commit protocols MUST each:

Specify the presumed abort protocol.
Support a read-only optimization, both as a response to Prepare, and as an unsolicited notification.
Support unsolicited rollback notifications from a participant.

The volatile two-phase commit protocol must:

Provide for completion of volatile phase 1 for all volatile participants before the durable two-phase commit protocol begins
Not preclude other participants from registering with either the volatile or durable two phase commit protocols until durable phase 1

It is not required to provide guarantees of notification of the transaction outcome.

The durable two-phase commit protocol must:

Preclude any additional two-phase commit registration as soon as the protocol enters durable phase 1 for any participant.
Guarantee notification of the transaction outcome, through the use of well- known recovery mechanisms, including repeated requests for outcome from the participant and repeated unsolicited notifications from the superior.

An individual participant may want to register for both two-phase-commit protocols with the same transaction, so this capability must be provided.

The Atomic Transaction specification security model must build on the security model defined in WS-Coordination.

The Atomic Transaction specification must define policy assertions that prescribe the transactional processing of SOAP messages on a WSDL operation. The assertions must be usable in the policy framework defined by WS-Policy. The assertions must have Operation Policy Subject and must be able to be attached to a WSDL binding.

These assertions must indicate whether:

A requester MAY, MUST or SHOULD NOT include an atomic transaction coordination context flowed with the message.
The target service processes its message under an atomic transaction regardless of whether the requester supplies an atomic transaction coordination context.

The WS-BusinessActivity specification consists of:

Definition of two coordination types suitable for coordination in a business activity protocol:
- A coordination type for which the outcome is the same for all participants involved in the same activity.
- A coordination type for which the outcome may vary between participants involved in the same activity.
Definition of two types of coordination protocols for consensual agreement:
- A coordination protocol in which participants inform their coordinator as to when they are complete.
- A coordination protocol in which a coordinator informs its participants as to when they are complete.

Both types of coordination protocols should:

Define a common, pair-wise consensus protocol that allows for eventual consensus between the pair of participants.
Use the coordinator to determine if the activity specified by the coordination context is to be canceled, has exited, has successfully terminated, requires compensation or has faulted.
Guarantee protocol notifications, through the use of well-known mechanisms including repeated unsolicited notifications. The Business Activity specification security model must build on the security model defined in WS-Coordination.

The Business Activity specification must define policy assertions that prescribe the business activity processing of SOAP messages on a WSDL operation. The assertions must be usable in the policy framework defined by WS-Policy. The assertions must have Operation Policy Subject and must be able to be attached to a WSDL binding.

These assertions must indicate whether:

The sender of an input message MAY, MUST or SHOULD NOT include an AtomicOutcome coordination context flowed with the message.
The sender of an input message MAY, MUST or SHOULD NOT include a MixedOutcome coordination context flowed with the message.

Out of Scope

The following is a non-exhaustive list. It is provided only for the sake of clarity. If some function, mechanism or feature is not mentioned here, and it is not mentioned as in-scope in the Scope of Work section either, then it will be deemed to be out of scope.

The TC will not define a mapping of the functions and elements described in the specifications to any programming language, particular messaging middleware or specific network transports.

Except for the elements directly related to the functions in the scope of the specifications, the TC will not prescribe the format of messages that are transferred according to the specifications.

The elements and/or mechanisms the TC defines must be independent of issues and considerations that do not affect an interoperable transaction coordination protocol. Specifically, the TC should not define mechanisms for binding the specifications to specific transports. However, the specifications should include elements and/or mechanisms that allow binding to transports commonly used in Web services implementations.

The TC will not attempt to define concepts or renderings for functions that are separable from consensus protocols, including but not limited to:

Security (Encryption, Integrity and Authentication)
Addressing
Policy languages and frameworks
Routing
General-purpose reliable message delivery

Where required, these functions are achieved by composition with other Web services specifications.

The TC will not attempt to define functionality duplicating that of a specification normatively referenced in the input WS-Coordination, WS-AtomicTransaction, or WS-BusinessActivity specifications. If the referenced specification is outside of a standardization process at the time this TC moves to ratify its deliverables, or is not far along enough in the standardization process, any normative references to it in the TC output will be expressed in an abstract manner, and the incarnation will be left at that time as an exercise in interoperability.

The TC will not specify changes to specifications external to the WS-TX input specifications.

For clarity, the out of scope features include, but are not limited to, the following:

Alternatives to two phase commit atomic commitment protocols
Heuristic outcome handling, including mixed outcome detection, in the atomic commitment protocols
Any pattern or optimization that leads to delegation of ownership of the outcome decision or re-orders the 2PC commit tree
The last-participant optimization
Any extension or protocol optimization beyond those already listed
Business process workflow or lifecycle specifications
Additional coordination types
Additional control protocols
Additional policy assertions
Additional protocols for activity management
Message formats or mechanisms other than SOAP messages defined in terms of XML InfoSets

Out of scope items for WS-TX may be appropriate for consideration by another TC, such as WS-CAF, in the context of the potential definition of one or more coordination types that extend WS-TX.

Deliverables

The TC has the following set of deliverables.

A WS-Coordination v 1.1 Protocol specification. Committee specifications are scheduled for completion within six months of the first TC meeting.
A WS-AtomicTransaction v 1.1 specification. Committee specifications are scheduled for completion within one year of the first TC meeting.
A WS-BusinessActivity v 1.1 specification. Committee specifications are scheduled for completion within one year of the first TC meeting.

These specifications will reflect refinements, corrections or material technological improvements with respect to the input documents and in accordance with this charter.

The WS-TX TC will first work on refining a WS-Coordination Committee Draft. Once this coordination framework Committee Draft has been completed, the TC will then work to refine the WS-AtomicTransaction and WS-BusinessActivity coordination type specifications.

Ratification of the above specifications as OASIS standards, including a brief period to address any errata will mark the end of the TC's lifecycle.

IPR Mode

This TC will operate under the "RF (Royalty Free) on RAND Terms" IPR mode as defined in the OASIS Intellectual Property Rights (IPR) Policy, effective 15 April 2005.

Anticipated Audience

The anticipated audience for this work includes:

Vendors offering web services products
Other specification authors that need distributed transactions for Web services
Software architects and programmers, who design, write or integrate applications for Web services and
End users implementing Web services-based solutions that require an interoperable, composable distributed transaction solution.

Language

TC business will be conducted in English.

Additional Information

The following additional information relates to the launch of the TC, but will not be part of the TC's charter.

Related Work

Since the WS-TX specifications are part of the Web services architecture, and must work well with other specifications within that architecture, the following [Applicable Work; Other, Similar Work] work may be relevant to this WS-TX TC.

Applicable Work

OASIS Web Services Security (WSS) TC. WS-TX will ensure that its specifications compose with the WSS TC specifications.
W3C Web Services Addressing WG. WS-TX will utilize the WS-Addressing functions where appropriate and avoid creating overlapping functions.

The TC may decide to establish liaisons with other groups as needed. Responsibilities for such liaison will be defined by the TC at that time.

Other, Similar Work

OASIS Web Services Business Process Execution Language (WSBPEL) TC. The WSBPEL TC focuses on an overall business process orchestration language. WS-TX will not discuss how an application operates internally, nor make any overall statement about a global orchestration, but will instead focus on individual, pair-wise message exchanges.
OASIS Web Services Composite Application Framework (WS-CAF) TC. WS-CAF also offers a set of consensus protocols, some of which are complementary to WS-TX. The WS-TX TC will focus on solidifying a proven foundation for an extensible coordination framework, and updating two fundamental consensus protocols, all of which have been publicly validated and interoperated on in the Web Services Protocol Workshops [18]. It will provide explicit rules in the form of state tables and message schemas for both successful and faulting behavior. It will offer an explicit security model for authorizing participation. It will emphasize composition with other WS-* standards, such as WS-Addressing and WS- Security.
OASIS Business Transactions (BTP) TC. The WS-TX TC will have a different focus with regard to specification scope, required functions, policy, and other Web Services composeability . WS-TX will focus solely on simple, pair-wise message exchange patterns that can be used to reach either atomic commitment, or looser application consensus. WS-TX will provide simpler interoperability by focusing exclusively on externally visible service behavior at the protocol level. It will not impose constraints on internal service implementations. It will emphasize clean composition with other WS-* standards, such as WS-Addressing and WS-Security. WS-TX will concentrate on interoperability specifying relatively few variations and providing simple state tables rather than extensive options with considerable application semantics.

Anticipated Contributions

The current WS-Coordination v 1.0 [1], WS-AtomicTransaction v 1.0 [2], and WS-BusinessActivity v 1.0 [3] specifications, as published August 2005 by Arjuna Technologies, BEA Systems, Hitachi, IBM, IONA Technologies and Microsoft are expected to be contributed to this TC.

Date and Time of First Meeting

The first meeting of the WS-TX TC will be a face to face meeting held in Cupertino, California on Wednesday November 16 and Thursday November 17, 2005, from 9:00 am to 5:30 local time. This meeting will be sponsored by Hitachi.

Ongoing Meeting Plans and Sponsors

It is anticipated the WS-TX Technical Committee will meet via teleconference every other week for 90 minutes at a time determined by the TC members during the TC's first meeting. It is anticipated that the WS-TX Technical Committee will meet in face to face every quarter at a time and location to be determined by the TC members. Actual pace of face to face and teleconference meetings will be determined by TC members.

One of the proposers, as listed below, will sponsor the teleconferences unless other TC members offer to donate their own facilities. If no other TC proposers offer to sponsor teleconference facilities, Microsoft or IBM will donate their facilities.

Proposers of the TC

Abbie Barbir, Nortel, abbieb@nortel.com
Rebecca Bergersen, IONA Technologies, Rebecca.bergersen@iona.com
Allen Brookes, Rogue Wave, abrookes@roguewave.com
Anto Budiardjo, Individual Member, antob@clasma.com
Dave Chappell, Sonic Software, chappell@sonicsoftware.com
David Connelly, Open Applications Group, Inc., dconnelly@openapplications.org
Paul Cotton, Microsoft Corporation, pcotton@microsoft.com
Glen Daniels, Sonic Software, gdaniels@sonicsoftware.com
Jean-Jacques Dubray, SAP, jean-jacques.dubray@sap.com
Petr Dvorak, Systinet, petr.dvorak@systinet.com
Dan Foody, Actional Corporation, dan.foody@actional.com
Robert Freund, Hitachi, Ltd., bob.freund@hitachisoftware.com
Tom Freund, IBM, tjfreund@us.ibm.com
Peter Furniss, Choreology peter.furniss@choreology.com
Alastair Green, Choreology, alastair.green@choreology.com
Paul Knight, Nortel, paul.knight@nortel.com
Chris Kurt, Microsoft Corporation, ckurt@microsoft.com
Mark Little, Arjuna Technologies, mark.little@arjuna.com
Denis Lussier, individual, denis@enterprisedb.com
Jeff Mischkinsky, Oracle, jeff.mischkinsky@oracle.com
Andrew Nash, Reactivity, anash@reactivity.com
Eric Newcomer, IONA Technologies, eric.newcomer@iona.com
Duane Nickull, Adobe Systems, dnickull@adobe.com
David Orchard, BEA, dorchard@bea.com
Sanjay Patil, SAP, sanjay.patil@sap.com
Alain Regnier, Ricoh, alain@ussj.ricoh.com
Ian Robinson, IBM, ian_robinson@uk.ibm.com
Tom Rutt, Fujitsu Software Corporation, trutt@us.fujitsu.com
Shivajee Samdarshi, TIBCO, shivajee@tibco.com
Hitoshi Sekine, Ricoh, hitoshi@ussj.ricoh.com
Keith Swenson, Fujitsu Software Corporation, kswenson@us.fujitsu.com
Claus von Riegen, SAP, claus.von.riegen@sap.com
Prasad Yendluri, webMethods, prasad.yendluri@webmethods.com

TC Convener

The TC Convener will be Paul Cotton (pcotton@microsoft.com) from Microsoft.

Proposed Co-Chairs

Ian Robinson (ian_robinson@uk.ibm.com) from IBM
Eric Newcomer (Eric.Newcomer@iona.com) from IONA

These co-chairs will jointly chair the WS-Coordination specification development, followed by the independent WS-AtomicTransaction and WS-BusinessActivity sub-tracks.

References

[1] WS-Coordination
http://schemas.xmlsoap.org/ws/2004/10/wscoor

[2] WS-AtomicTransaction
http://schemas.xmlsoap.org/ws/2004/10/wsat

[3] WS-BusinessActivity
http://schemas.xmlsoap.org/ws/2004/10/wsba

[4] "Transaction Processing: Concepts & Technologies", Jim Gray and Andreas Reuter Morgan Kaufmann, 1993.

[5] "Principles of Transaction Processing," Philip A. Bernstein and Eric Newcomer, Morgan Kaufmann, 1997.

[6] WS-Security
http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-soap-message-security-1.0.pdf

[7] WS-Trust
http://schemas.xmlsoap.org/ws/2005/02/trust

[8] WS-SecureConversation
http://schemas.xmlsoap.org.ws/2005/02/sc

[9] WS-Addressing
http://www.w3.org/Submission/2004/SUBM-ws-addressing-20040810/

[10] SOAP 1.1
http://www.w3.org/TR/2000/NOTE-SOAP-20000508/

[11] SOAP 1.2
http://www.w3.org/TR/2003/REC-soap12-part1-20030624/