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3G-324M is the 3GPP umbrella protocol for video telephony in 3G mobile networks. The 3G-324M protocol operates over an established circuit switched connection between two communicating peers. 3G-324M is an umbrella specification to enable conversational multimedia communication over Circuit Switched (CS) networks and has been adopted by the 3GPP. 3G-324M is based on the ITU-T H.324 specification for multimedia conferencing over Circuit switched networks.〔(IMTC Press Coverage ), International Multimedia Telecommunications Consortium (IMTC), April 1, 2001 to November 16, 2004.〕〔Orr, Eli. (News & Analysis: Understanding The 3G-324M Spec ), EETimes.com website. January 21, 2003.〕 3G-324M is composed of the following sub-protocols: * ITU-T H.245 for call control * ITU-T H.223 for bit streams to data packets multiplexer/demultiplexer * ITU-T H.223 Annex A and B for error handling of low and medium BER detection, correction and concealment * ITU-T H.324 with Annexes A and C for operating in wireless environment The 3G-324M specification using the Circuit switched network allows delay sensitive conversational multimedia services such as: * Videoconferencing for personal and business use * Multimedia entertainment services * Telemedicine * Surveillance * Live Video Broadcasting– Cable TV On-the-Go * Video-on-demand (movies, news clips) 3G-324M is agnostic to the actual Circuit switched network that uses it. It can run as easily over UMTS as well as TD-SCDMA networks. 3G-324M is a proven solution for conversational multimedia based services that packet-based wireless networks cannot deliver because of inherent overhead, BER sensitivity, and variant routing delays. 3G-324M operating over a circuit switched channel between two communication peers guarantees the fixed-delay quality of service for multimedia communications. Combining Circuit switched 3G-324M services with packet-based SIP services such as presence can leverage the strength of both networks to enable new types of differentiated and innovative mobile 3G services. == Codecs == Audio Codec * GSM Adaptive Multi-Rate, mandatory * AMR-WB (G.722.2), optional * ITU-T G.723.1, optional Video Codec * ITU-T H.263, mandatory * ITU-T H.261, optional * MPEG-4 part 2 simple profile 1 level 0, optional * ITU-T H.264, optional 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「3G-324M」の詳細全文を読む スポンサード リンク
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