Security is an essential part of any Web service. Rational Application Developer allows you to take advantage of security standards and without too much effort create all of the necessary parameters to add security to your services. This tutorial shows you how to authenticate using a user ID and password, ensure integrity using digital signatures, and ensure confidentiality using encryption. and It is important to distinguish between security mechanisms that are transport dependent and those that are transport independent. Developers often strive to ensure that their services are not bound to any particular transport. If your security model is based on the transport, you are indirectly tightly coupling your service, should you need it to be secure, to a fixed protocol.