nne's Web page (Figure A-2) is the one you are looking for (http://www.cs.columbia.edu/sip). Schulzrinne, one of the co-author's of SIP, maintains this Web page and it is unarguably the best page to follow SIP development. The "news" sec- tion contains information about SIP-related important events such as the release of a new RFC, or links to the organizers of the next SIP interoper- ability event. Schulzrinne's Web page also contains links to different orga- nizations making use of SIP and to different presentations given in different telecommunications conferences. It is worthwhile to spend some Appendix Figure A-2 http://www.cs. columbia.edu/sip Session Initiation Protocol (SIP) SIP, the Session Initiation Protocol, is a signaling protocol for Internet conferencing, telepony, presence, events notification and instant messaging. SIP was developed within the IETF MMUSIC (Multiparty Multimedia Session Control) working group, with work proceeding since September 1999 in the IETF SIP working group. A number of standardization organizations and groups are using or considering SIP: IETF PINT working group 3GPP for third-generation wireless networks Softswitch Consortium IMTC and ETSI Tiphon are working onSIP-H.323 interworking PacketCable DCS (distributed call signaling) specification 3GPP (for third-generation wireless) SpeechLinks, for moving between speech-enabled sites May 29, 2001: RFC2543bis (-03) draft May 4, 2001: Information about the 8th SIP Interoperability Test Event is now available April 14, 2001: search feature added. April 11, 2001: The SIP interoperability test event has a new logo, courtesy of Ubiquity. SiPit sa ⑉ - April 10, 2001: RFC 3087 (Control of Service Context using SIP Request-URI) published Feb. 1, 2001: RFC 3050 (Common Gateway Interface for SIP) published Nov. 30, 2000: Caller preferences draft in WG last call until December 24, 2000 Nov. 29, 2000: Guidelines for Authors of SIP Extensions draft in WG last call until December 24, 2000 November 24, 2000: RFC2543bis (-02) draft Nov. 17, 20