Message Exchange Patterns (MEPs)
- <operation>
specifies message types and desired MEP
- MEP
defines a pattern of interaction between agents
- WSDL 2.0 defines base set of MEPs:
- in-out, in-only, out-in, out-only
- robust-in-only, robust-out-only (permit optional fault)
- out-opt-in (out followed by optional in)
- Each MEP is identified by a URI
- Extensible: Other MEPs can also be used (identified by URI)