W3C Architecture DomainWeb Services Activity

Web Services Addressing Working Group Charter

[October 2006]

Bob Freund (Hitachi, Ltd.), Chair,
Philippe Le Hégaret, Team Contact

Note: This is the third charter for the Web Services Addressing Working Group. The previous charter is still available.

The Working Group follows the rules and requirements of the latest operative version of the World Wide Web Consortium Process Document. In the event of a conflict between this document and the W3C Process Document, the W3C Process Document shall take precedence.

Table of Contents

  1. Mission
  2. Scope
  3. Deliverables
  4. Duration
  5. Expected milestones
  6. Coordination with Other Groups
  7. Related Specifications
  8. Working Group participation
  9. Meetings
  10. Decision policy
  11. Communication
  12. Confidentiality
  13. Patent Policy


The purpose of the Web Services Addressing Working Group, part of the Web Services Activity, is to produce a W3C Recommendation for Web Services Addressing by refining the W3C Member Submission "WS-Addressing" based on consideration of the importance of this component in the Web Services architecture, implementation experience, and interoperability feedback. WS-Addressing defines how message headers direct messages to a service or agent, provides an XML format for exchanging endpoint references, and defines mechanisms to direct replies or faults to a specific location.

These facilities are expected to be broadly available and should be provided on a timely fashion. Therefore, this Working Group shall be schedule-driven. This charter features an aggressive schedule and a tightly constrained scope designed to ensure that the Working Group will meet its schedule. This charter is intended to carry WS-Addressing consensus and interoperability forward, as outlined in Tips for Getting to Recommendation Faster.


The Working Group is chartered to standardize the mechanisms for referencing and addressing Web services by refining WS-Addressing, which includes the following components of the Web Services Architecture:

  1. The means by which message headers are used to direct messages to a Web service or agent.
  2. Abstract message properties which include:
  3. An XML Infoset for communicating the information necessary to generate appropriate headers to direct messages to a service or an agent including:
    • a URI designating the destination address;
    • service specific message headers;
    • interaction specific message headers;
    • WSDL definitions relevant to this service;
    • additional metadata as required.

    Note: the Architecture of the World Wide Web, First Edition indicates that distinct resources must be assigned to distinct URIs. This must be considered when refining the mechanism for the service specific message headers.

  4. Abstract properties to identify subsequent destinations in the message exchange, including:
    • the reply destination,
    • the fault destination.

The components must be extensible to enable other mechanisms such as new kinds of relationships between correlated messages, policies, or service semantics to be built upon Web Services Addressing. The components must also be usable independently of the SOAP or WSDL version in use.

In addition, the Working Group is chartered to define:

  1. A binding of all abstract message properties to SOAP 1.1 and SOAP 1.2 headers.
  2. The use of these abstract message properties in the context of all WSDL 1.1 or WSDL 2.0 Message Exchange Patterns, including the asynchronous use of these MEPs. In particular, the relationship between message properties and WSDL 1.1 and WSDL 2.0 service descriptions will be provided if applicable.
  3. A security model for using and communicating these abstract properties.

The components must be defined so as to allow binding to protocols other than SOAP.

The deliverables for the SOAP 1.1 and WSDL 1.1 bindings must include language that the bindings are defined for backward compatibility only.

Out Of Scope

While the definition of new WSDL MEPs, composition of MEPs, or interaction patterns, such as pub-sub, callback or notification mechanisms, is outside the scope of the Web Services Addressing Working Group, the Working Group shall accomodate the use of the addressing mechanism in the context of such scenarios. The Working Group should coordinate with other groups wishing to define such interaction patterns.



The expiration date of this charter is 30 June 2007.

Expected milestones

The Working Group should coordinate with the Web Services Description Working Group to define the use of message headers in the context of WSDL 2.0 Message Exchange Patterns and to support the definition of Web Service Addressing property values in WSDL 2.0 service descriptions. To ensure that coordination with WSDL 2.0 does not delay the schedule for the core WS-Addressing functionality the Working Group must produce a separate specification for the WSDL 1.1 and 2.0 bindings.

April 2007
Proposed Recommendation for the Web Services Addressing WSDL 1.1 and WSDL 2.0 Binding specification.
June 2007
Recommendation for the Web Services Addressing WSDL 1.1 and WSDL 2.0 Binding specification.

In case of significant schedule changes, the Advisory Committee MUST be notified of any significant schedule changes.

Coordination with Other Groups

W3C Groups

The Working Group should coordinate its efforts with the W3C Working Groups involved in the Web Services Activity, especially:

XML Protocol Working Group
The binding of message properties to SOAP headers provided by the Web Services Addressing Working Group uses facilities defined by SOAP 1.2.
Web Services Description Working Group
WSDL 2.0 provides a description component for a Web service, and thus one must be able to use WS-Addressing with services described by WSDL 2.0.
Web Services Choreography Working Group
Choreography defines message flows over multiple domains of control that may make use of WS-Addressing.
Web Services Coordination Group
The Working Group Chair will participate in the Web Services Coordination Group.
The specification defined by the Web Services Addressing Working Group shall be aligned with the World Wide Web architecture as defined by the Technical Architecture Group (e.g. mapping qnames to URIs).

External Groups

The following organizations have groups that may utilize the Web Services Addressing:

Organization for the Advancement of Structured Information Standards
OASIS is a not-for-profit, international consortium that drives the development, convergence and adoption of e-business standards. Relevant Technical Committees include WS-BPEL, WS-Security, WS Distributed Management, Web Services Reliable Exchange (WS-RX), WS Reliable Messaging, WS Composite Application Framework, WS-Resource Framework, and WS-Notification.
Web Services Interoperability Organization
The Web Services Interoperability Organization is an open industry effort chartered to promote Web Services interoperability across platforms, applications, and programming languages through the development of profiles, any one of which could be relevant.

Related Specifications

WS-MessageDelivery is a W3C Member Submission and may provide a source of comment and review on WS-Addressing.

Working Group participation

Effective participation is expected to consume one workday per week for each Working Group participant; two days per week for editors. The Chair shall ensure that the criteria for Good Standing are understood and followed.

To be successful, we expect the Web Services Addressing Working Group to have 10 or more active participants for its duration.

Participants are expected to carry out their assignments in a timely fashion, attend most meetings, and to remain familiar with group documents and mailing list discussion (W3C Process Document, section Active participation will help ensure rapid progress.


The Chairs of this Working Group are Bob Freund (Hitachi Ltd.) and Mark Nottingham (Yahoo! Inc.).

The Chair is expected to use the means provided by the W3C Process to help the Working Group remain on schedule and avoid scope creep (see the list of expected milestones). The Chair will:

  1. Ensure that, when setting the agenda, discussion items are within the scope of the chartered deliverables.
  2. Ensure issues are decided in a timely fashion, after due consideration of all opinions and positions.
  3. Reconsider a decision only when presented with new information. (W3C Process Document, section 3.3.4).
  4. Ensure frequent publication of Recommendation Track documents (W3C Process Document, section 6.2.7).

W3C Team resources

The initial W3C Team contacts are Hugo Haas and Philippe Le Hégaret. It is expected that this Working Group would consume about 0.30 FTE, including administrative logistics.


The Working Group will have distributed and face-to-face meetings.

At least up until the Last Call period ends, a two-hour Working Group distributed meeting will be held every week. When necessary to meet agreed-upon deadlines, distributed meetings may be held twice a week. Face-to-face meetings are expected to happen every 6 weeks. Thereafter, a one- to two-hour Working Group distributed meeting will be held every week. When necessary to meet agreed-upon deadlines, distributed meetings may be held twice a week. Face-to-face meetings are expected to happen every 2 months.

Decision policy

When deciding a substantive technical issue, the Chair may put a question before the group. The Chair must only do so during a group meeting, and at least 50% of participants in Good Standing must be in attendance.

As explained in the Process Document (section 3.3), the Working Group will seek to make decisions when there is consensus. When the Chair puts a question and observes dissent, after due consideration of different opinions the Chair should record a decision (possibly after a formal vote) and any objections, and move on.

When the Chair conducts a formal vote to reach a decision on a substantive technical issue, eligible voters may vote on a proposal one of three ways: for a proposal, against a proposal, or abstain. For the proposal to pass, there must be more votes for the proposal than against. In case of a tie, the Chair will decide the outcome of the proposal.


The Working Group will utilize a public mailing list, public-ws-addressing@w3.org.

A Member-only mailing list member-ws-addressing@w3.org is also available for administrative purposes only.


The proceedings of this Working Group are public, subject to exceptions made by the Chair, after consultation with the Working Group.

Patent Policy

This Working Group operates under the W3C Patent Policy (5 February 2004 Version). To promote the widest adoption of Web standards, W3C seeks to issue Recommendations that can be implemented, according to this policy, on a Royalty-Free basis.

Philippe Le Hégaret
Last modified $Date: 2007/01/17 10:45:44 $