You can create multiple WSA instances. You might do this to support different versions of the Web service or different levels of security. Suppose you have several AppServer applications to deploy as Web services, and you want only a particular group of users to have access to each Web service. You can accomplish this by creating a WSA instance for each group of users, then deploying to each WSA instance the Web services for that group. For more information on this and other security techniques, see Web Services Adapter Security Configurations.