IMHO, this is one of those areas where the requirements differ depending
upon whether we are talking about a host->device protocol, or the more
general client->server protocol.
In the case of a host->device protocol, I agree 100%... the host should
be able to register for specific event types, where the event associated
with each event type has some fixed, standardized content. This is
along the lines of what was discussed in the JMP meeting in Austin.
However, in the more general client->server case, I think that variable
content is an important requirement. Specifically, I think that it is
important that the notification be capable of holding enough information
such that the client does *not* have to go back and query the server to
get what it needs. Seeing as how we cannot mandate what information the
client should be interested in, this implies that we should allow the
client to specify its interest. Furthermore, if we are to allow vendors
to extend IPP, then the only way that clients can get at that extended
information in a notification is if we allow the client to ask for what
one man's opinion...
-- Jim Walker <email@example.com> System Architect/DAZEL Wizard DAZEL Corporation, Austin, TX