Changes

There will be many IPC protocols, and they should all be as error-free as possible by design. Having separate protocols for separate uses is a good thing, and they all shouldn't be multiplexed by hand over a shared transport layer. Further, protocol Protocol implementations should only have to check for errors as infrequently as possible; the heavy lifting should be done generically, or by code generated from high-level specifications. Finally, explicit protocols make automatically generating test cases (of "normal" ''and'' "failure" conditions) much easier.