> The ordering of elements is the _only_ information about the > processing sequence. How could the receiver otherwise > determine that it should first check Signature, then decrypt?
I agree somewhat, but note it says SHOULD, not MUST, which means a different processing order is still valid WSS. Normally, WSS processing requirements would be expressed in some policy (e.g., WS-Policy and its derivates, or perhaps just a business agreement between parties) or by stated adherence to a profile (e.g., WS-I BSP 1.0, which coincidentally changes the SHOULD above to a MUST). An application that ad-hoc processes WSS messages should probably be considered broken from a security point of view. Hans
