Subject: White paper on interaction of SIP and resource reservation

From: Henning Schulzrinne <[email-masked]>
Date: Fri, 11 Jun 1999 21:08:57 -0400

See http://www.cs.columbia.edu/~hgs/sip/drafts/resource.pdf

Comments are appreciated. The Internet draft will follow shortly.

Thanks.

Henning

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From: Jon Crowcroft <[email-masked]>
Date: Fri, 18 Jun 1999 15:36:44 +0100

Henning

ok - so to create the same "atomic" "user-user+user-net" signal out of
the three piece suite that is
sip + (rsvp a->b +rsvp b->a)
clearly we need to have 2 phases at least
sip request + sip commit
and
rsvp tentative request/probe + rsvp commit

then we need to unravel the two questions of 
reservation theft of service versus
reservation denial of service

clearly, given all this is motivated by megaco or voip/pstn gateways,
theft of service is a bigger threat than denial, so we need to err i
noru design in favour of denial, and then engineer solutins for
limiting the denial of service dfamge (e.g. limit the rate of
tentative rsvp state setup to some maxmimum is the nornmal telephony
signalling type hack)...

so with this abstraction, i think there are two alternateives to your
proposals in the paper above - i leave these as an excercise for the
student...

 cheers

   jon