Accessing Secured Web Services from Windows SharePoint Services Applications

In a service-oriented environment, managing the security credentials for an application that is accessing a Web service is a critical issue. This article describes how you can use the Kerberos version 5 authentication protocol and impersonation to secure a Web service accessed by a SharePoint application to ensure that only properly authenticated and authorized users have access to the Web service in Windows Server 2003 and Windows Server 2000 environments