If you want to understand the different security aspect in Web Services I recommend you this new cool MSDN Article: How to use Web Services Enhancements 2.0 to implement security, trust, and secure conversations in Web services architecture.
If you want to understand the different security aspect in Web Services I recommend you this new cool MSDN Article: How to use Web Services Enhancements 2.0 to implement security, trust, and secure conversations in Web services architecture.