Web Services Architecture Requirements

March 04 2002

This version:
http://www.w3.org/2002/ws/arch/2/wd-wsawg-reqs-0220304.html
Latest version:
http://www.w3.org/someplaceoranother
Previous version:
http://www.w3.org/2002/ws/arch/2/wd-wsawg-reqs-02202002.html
Editors:
Daniel Austin, W. W. Grainger, Inc. <austin.d@ic.grainger.com>
Abbie Barbir, Nortel Networks, Inc. <abbieb@nortelnetworks.com>
Sharad Garg, The Intel Corporation <sharad.garg@intel.com>

NOTICE:

This draft is provided to the working group for discussion only and represents a very early version of this document. Readers may well expect significant changes in content and organization over time.

NOTICE:

The key words "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.

Abstract

The use of Web Services on the World Wide Web is expanding rapidly as the need for application-to-application communication and interoperability grows. These services provide a standard means of communication among different software applications involved in presenting dynamic context-driven information to the user. In order to promote interoperability and extensibility among these applications, as well as to allow them to be combined in order to perform more complex operations, a standard referernce architecture is needed. The Web Services Architecture Working Group at W3C is tasked with producing this reference architecture.

This document describes a set of requirements for a standard reference architecture for Web Services developed by the Web Services Architecture Working Group. These requirements are intended to guide the development of the reference architecture and provide a set of measurable constraints on Web Services implementations by which conformance can be determined..

Status of this Document

This document is an editors' copy that has no official standing.

This section describes the status of this document at the time of its publication. Other documents may supersede this document. The latest status of this series of documents is maintained at the W3C. .

This document is a preliminary editor's draft of the Web Services Architecture Working Group which is part of the Web Services Activity.

The Working Group intends that this document will at some point become a Working Draft.

The Web Services Architecture Working Group will not allow early implementation to constrain its ability to make changes to this document prior to final release. Publication as a Working Draft does not imply endorsement by the W3C Membership. It is inappropriate to use W3C Working Drafts as reference material or to cite them as other than "work in progress". A list of current W3C Recommendations and other technical documents can be found at http://www.w3.org/TR/.

Comments on, and discussions of this draft can be sent on the (archived) public mailing list www-ws-arch@w3.org.

This document may be available in translations in the future. The English version of this specification is the only normative version.

Due to the architectural nature of this document, it affects not only a large number of W3C Working Groups, but also software developers, content developers, and writers and users of specifications outside the W3C that have to interface with W3C specifications.

Table of Contents

1 Introduction
    1.1 What is a Web Service?
2 Requirements Analysis Method
    2.1 Understanding Critical Success Factors Analysis
    2.2 The Analysis Heirarchy
        2.2.1 Mission, Vision, and Values
        2.2.2 Goals
        2.2.3 Assumptions and Information Needs
        2.2.4 Problems and Gap Analysis
        2.2.5 Critical Success Factors
        2.2.6 Requirements and User Scenarios
        2.2.7 Analysis Matrix: Problems v. CSFs
3 Requirements
4 User Scenarios
5 Glossary
6 Acknowledgements
7 References
    7.1 Normative References
    7.2 Informative References


1 Introduction

1.1 What is a Web Service?

"A web service is is a software application or component that can be accessed over the Internet using a vendor/platform/language-neutral data interchange format to invoke the service and supply the response, using a rigorously defined message exchange pattern, and producing a result that is sufficiently well-defined to be processed by a software application."

2 Requirements Analysis Method

2.1 Understanding Critical Success Factors Analysis

2.2 The Analysis Heirarchy

2.2.1 Mission, Vision, and Values

2.2.2 Goals

A note on the naming convention used here and throughout this document: all goals, critical success factors and requirements are labelled according to the following convention:

[D-]A(G|F|R)nnnn.

[D-] indicates that the item is in a draft state.

A indicates that this is an architectural item.

[G|F|R] is one of Goal|Critical Success Factor|Requirement.

nnnn indicates the sequence number of the item.

Sorry for the bad formatting of this note.

Proposed Goals for the Web Services Architecture Working Group

To develop a standard reference architecture for web services that:

D-AG0001

ensures the interoperability of web services software products from different implementors based on well-defined standards

D-AG0001-a

provides a complete reference framework that encourages the development of interoperable software products from multiple vendors and provides a defensible basis for conformance and interoperability test suites

D-AG0002

provides modularity of web services components, allowing for a level of granularity sufficient to meet business goals

D-AG0003

is sufficiently extensible to allow for future evolution of technology and of business goals

D-AG0004

ensures platform independence of web services components in a way that does not preclude any programming model nor assume any particular mode of communication between the individual components

D-AG0005

provides simplicity and ease-of-use that does not impose high barriers to entry for users of web services

D-AG0006

addresses the security of web services across distributed domains and platforms

D-AG0007

is reliable, and stable, and whose evolution is predictable over time

D-AG0008

is coherent and consistent in its definition

D-AG0009

is aligned with the semantic web initiative at W3C and the overall existing web architecture

D-AG0010

uses W3C XML technologies in the development of the web services architecture to the extent that this is compatible with the overall goals listed here.

D-AG0011

is consistent with the existing web and its heterogenous environment and distributed architecture to the greatest extent possible

In addition, the Working Group will also act to:

D-AG0012

identify or create the use cases that validate the requirements and the web services architecture and illustrate the benefits of web services

D-AG0013

co-ordinate the development of web services within W3C, together with other W3C Working Groups where there is overlap among their problem domains

D-AG0014

serve as liaison with groups outside W3C who are working on web 0services in order to achive interoperability and reduce duplication of effort

D-AG0015

organize its efforts in such a way as to adress vital time-to-market issues for its products, including iterating over successive refinements of the overall requirements for the standard reference architecture.

D-AG0016

identify current gaps in architectural interoperability and recommend standards -based remedies.

2.2.3 Assumptions and Information Needs

2.2.4 Problems and Gap Analysis

2.2.5 Critical Success Factors

2.2.6 Requirements and User Scenarios

2.2.7 Analysis Matrix: Problems v. CSFs

3 Requirements

4 User Scenarios

5 Glossary

6 Acknowledgements

7 References

7.1 Normative References

7.2 Informative References