Appendix A: Guide to a Subset of the Proposed SOA Standards (WS-)

Overview

A variety of standards are being developed to provide the runtime Quality-of-Service (QoS) support that applications often need when they interact with Web services. The industry refers to this group of specifications by the abbreviation WS-* (sometimes called WS splat). In many cases, the standards affect the composition of SOAP header blocks or runtime configuration files.

Standards are written for multiple purposes. To communicate, in a shorthand way, how a given SOA runtime product uses a set of standards, the vendor may indicate that the product adheres to one or more profiles. A profile lists the supported standards and describes profile requirements. Each requirement is a rule indicating how some aspect of a given standard applies to any product that is in conformance with the profile. One requirement might state that the product must always use a specific, optional feature of the standard. A second requirement (sometimes called a restriction) might state that the product must never use a specific, optional feature of the standard. The purpose of profiles is to make the technology more consistent for a given use and to promote Web service interoperability.

A particularly important profile is the Web Services Interoperability Organization (WS-I) Basic Profile, which clarifies the use of Web Services Description Language (WSDL) and SOAP. For details on that profile and on the sponsoring organization, see the following Web site: http://www.ws-i.org.

This appendix lists more than a dozen WS-* specifications in an order that highlights the most widely accepted ones. People may have different opinions on our choices, and the situation will change, but here's our list of greatest hits:

• WS-Addressing

• WS-Policy

• WS-ReliableMessaging

• WS-Security family of specifications

• WS-MetadataExchange

• WS-AtomicTransaction

• WS-BusinessActivity

• WS-Coordination

• Web Services Unified Management (WS-UM), which relies on

  • Web Services Distributed Management (WSDM)

  • WS-Management

• WS-EventNotification, which relies on

  • WS-Notification, including WS-BaseNotification, WS-BrokeredNotification, and WS-Topics

  • WS-Eventing

• Web Services Resource Transfer (WS-RT), which relies primarily on WS-Transfer

• WS-ResourceFramework

• WS-Enumeration

• Web Services for Remote Portlets

• WS-Agreement (which is little used, but quite interesting)