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[12] "Http://www.ietf.org/rfc/rfc2833.txt." Web.

[13] Nerd Vittles. Web. 23 Nov. 2009. .

[14] "RFC 1889 - RTP: A Transport Protocol for Real-Time Applications." IETF Tools. Web. 23 Nov. 2009. .

[15] "RFC 2326 - Real Time Streaming Protocol (RTSP)." IETF Tools. Web. 23 Nov. 2009. .

[16] "RFC 2327 - SDP: Session Description Protocol." IETF Tools. Web. 23 Nov. 2009. .

[17] "RFC 3261 - SIP: Session Initiation Protocol." IETF Tools. Web. 23 Nov. 2009. .

[18] "Session Initiation Protocol -." Wikipedia, the free encyclopedia. Web. 23 Nov. 2009. .

[19] Sinnreich, Henry, and Alan B. Johnston. "Chapter 2 - Internet Communications Enabled by SIP". Internet Communications Using SIP: Delivering VoIP and Multimedia Services with Session Initiation Protocol, Second Edition. John Wiley & Sons. © 2006. Books24x7.

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[24] "What is Voip - Cisco - Cisco Systems." Cisco Systems, Inc. Web. 23 Nov. 2009. .