WS-SecureConversation
WS-SecureConversation is a Web Services specification, created by IBM and others, that works in conjunction with WS-Security, WS-Trust and WS-Policy to allow the creation and sharing of security contexts. Extending the use cases of WS-Security, the purpose of WS-SecureConversation is to establish security contexts for multiple SOAP message exchanges, reducing the overhead of key establishment.
Features
- Establish a new security context in following modes:
- * Security context token created by a security token service
- * Security context token created by one of the communicating parties and propagated with a message
- * Security context token created through negotiation/exchanges
- Renew security context
- Amend Security context
- Cancel security context
- Derive key: parties may use different keys per side and function, and change keys frequently to prevent cryptographic attacks
- Maintain high secure context
Pros/Cons
Following a pattern similar to TLS, WS-SecureConversation establishes a kind of session key. The processing overhead for key establishment is reduced significantly when compared to WS-Security in the case of frequent message exchanges.However, a new layer is put on top of WS-Security, that implies other WS-* protocols like WS-Addressing and WS-Trust. So the importance of performance has to be compared to the added complexity and dependencies.
See the performance section in WS-Security.