[ambiguity] mcp version & mcp-negotiate version

[Richard Godard <richard.godard@tecfa.unige.ch>]

New day, new questions & comments :)

There is a little ambiguity/problem with the startup requence of the MCP
protocol: you HAVE TO start using the mcp-negotiate package without knowing
what version to use.

An fix would be to specify this during the initial handshake with the mcp
messages (I mean the #$#mcp .... messages)
Another fix is to tie the version of the mcp-negotiate package with the MCP
version, but then that remove flexibility to the mcp-negotiate package...

Maybe the cleanest fix could to change the mcp-negotiate specs slightly so
that starting with version 2.0 the FIRST mcp-negotiate-can message sent to
the other endpoint MUST be the mcp-negotiate version and that you should
wait for the other endpoint to send you (or lack of sending you, see
bellow) an mcp-negotiate-can for its version of the mcp-negotiate package
before sending the other mcp-negotiate-can for the other supported packages.
This would work perfectly AND if the other endpoint only support version
1.0 offer an easy way to detect it: you would know it's a 1.0 version
because it wouldn't send the mcp-negotiate-can ... package: negotiate-can
as first mcp-negotiate-can message.

Does it make sense?

Richard