RE: [Sip] sip-session-timer-11: why explicitly impose proxy restr ictions on all the b2bua's

[Adam Roach <adam@dynamicsoft.com>]

I think the major point is that, with B2BUAs, all bets are off.
As long as they look like SIP UAs on both sides, they meet
spec. There's nothing we can do about this. Cullen points
out exactly what I was going to. I'll expand on this some.

I have a SIP phone on my desk. So does Alan. However,
because I'm lazy, I often pick up my SIP phone and call
his normal PSTN number. That goes to my PSTN gateway,
through the PSTN to Alan's gateway, and rings Alan's
SIP phone.