81This chapter provides an overview of the Internet protocol architecture for
real-time multimedia. Other key Internet transport and multimedia protocols
besides SIP, such as IP unicast and multicast transport protocols, RTP/RTCP,
SDP, and RTSP, are briefly introduced.
Introduction
Though the Internet was not created primarily for real-type communications,
and its initial growth has been driven mainly by file transfer, e-mail, data, and
the World Wide Web, multimedia on the Internet has also seen tremendous
growth for various applications, including (but not limited) to telephony.
Indeed, many online magazines routinely carry links to streaming audio or
streaming audio/video news clips, movie trailers, or online tutorials and pre-
sentations. Video services on the Internet are emerging strongly. There are an
ever-increasing number of radio and video stations worldwide on the Internet,
rivaling the number of stations on shortwave radio. The Internet has shown its
capability of:
■■ Consolidating all types of media and data on one single network
■■ Integrating all services at the application layer for information, commu-
nications, entertainment, and transactions