Introduction to web services extensions
Web services extensions are used to provide additional capabilities to web services. For example, if we want to protect web services from unauthorized access, we can make use of the relevant web services extension. Web services extensions are usually governed by a set of specifications referred to as the WS-* standards. For example:
WS-Addressing
WS-Policy
WS-Security
WS-ReliableMessaging
WS-Discovery
WS-Transfer
WS-AtomicTransaction
There are different types of specifications which address various aspects of web services in order to extend the core features. These specifications are governed by various standard bodies such as W3C (http://www.w3.org/) and OASIS standards (https://www.oasis-open.org/standards).
Web service frameworks adhere to most of these specifications in order to be interoperable with each other. For example, Apache Axis2 implemented WS-Security specification; so, we can communicate with any service that is deployed on Axis2 via a .NET service...