The Routing Over Large Clouds Mailing List Archive by date

[Joel Halpern <jhalpern@newbridge.com>]

I think that there is one other aspect of the situation here.
One of the thinks which is not necessarly agreed, but which I assume, is
that it is better for the system if long-lived communications use direct
VCs.  This is not a matter of meeting the users QoS requirements, but of
using the system resources effectively.

Thus, I tend to think of QoS as only one part of the reason for doing
direct VCs. 

This leads, to my thinking, to a document (the APR document under
discussion) whcih discusses when one wants direct VCs.  The important
observations (I think) are:
1) That the desire for direct VCs is not coupled to whether the source
    and destination are in the same "address aggregate".  In particular, 
    it is independent of whether they are in the same lowest level
    "address aggregate" (traditionally known as "subnet").
2) That the communicating host, informated by the policy of the system
    and the QoS requested by the user/application is in the best position
    to decide when to establish direct VCs.

There are a number of implications here.  Among them are a chnage in the
meaning of the notion of "subnet" towards a notion oriented towards address
management rather than communications management.
Another aspect is that some lower level system in the host will need
information about the user/applications desires and expectations for
communications.  Initial implementations may get this from some combination
of port numbers, RSVP, and magic.  Later? ...

I think getting these points documented is very useful for us.
And they are certainly not duplicative with current RSVP or Int-Serv work.

Yours,
Joel M. Halpern				jhalpern@newbridge.com
Newbridge Networks Inc.