References
SIP Related
Henning Schulzrinne's Marvelous SIP Page
http://www.cs.columbia.edu/sip/
Tech-Invite SIP site with grammars, registrations, much coolness
http://www.tech-invite.com
Slides on rfc2543-bis work from fall 2001 SIPIT.
ppt
SIPIT-10 Slides from Robert Sparks
ppt
Changes in SIP from bis09 to RFC3261 -- Jonathan Rosenberg
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