Requirements on lower layers (was Versioning and namespaces)

[Rich Salz <rsalz@caveosystems.com>]

On Jan 23, Dick Brooks wrote:
> I'm not suggesting that ebXML exclude SMTP. I'm suggesting that the
> MHS spec address transport specific issues in transport specific
> sections as opposed to placing transport specific information in the
> main body of the spec. Each transport section would define how
> to "prepare" an ebXML message for transport.

Except that you have to be aware of the requirements that you might be
placing on the lower layers.  Perhaps a better example is MSH-to-MSH
acknowledgements.  If using HTTP, then the sender can do a POST and get
a "rich" ebXML document back synchronously, over the same connection. 
If using SMTP, then the sender can send the message and
	Get a "250" back (SMTP success code, meaning message queued)
	Get a rich reply only if speaking to a custom SMTP server
	Wait for an asychronous mailed-back acknowledgement

This could have implications for the ping/pong messages, e.g.
	/r$