3G-324M is the

3GPP The 3rd Generation Partnership Project (3GPP) is an umbrella term for a number of standards organizations which develop protocols for mobile telecommunications. Its best known work is the development and maintenance of: * GSM and related 2G and ...

umbrella protocol for

video telephony Videotelephony (also known as videoconferencing or video calling) is the use of audio and video for simultaneous two-way communication. Today, videotelephony is widespread. There are many terms to refer to videotelephony. ''Videophones'' are ...

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

. 3G-324M is based on the

ITU-T The International Telecommunication Union Telecommunication Standardization Sector (ITU-T) is one of the three Sectors (branches) of the International Telecommunication Union (ITU). It is responsible for coordinating Standardization, standards fo ...

H.324 specification for multimedia conferencing over

Circuit switched Circuit switching is a method of implementing a telecommunications network in which two network nodes establish a dedicated communications channel ( circuit) through the network before the nodes may communicate. The circuit guarantees the full ...

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

network allows delay sensitive conversational multimedia services such as: *

Videoconferencing Videotelephony (also known as videoconferencing or video calling) is the use of audio signal, audio and video for simultaneous two-way communication. Today, videotelephony is widespread. There are many terms to refer to videotelephony. ''Vide ...

for personal and business use * Multimedia entertainment services * Telemedicine * Surveillance * Live Video Broadcasting– Cable TV On-the-Go *

Video-on-demand Video on demand (VOD) is a media distribution system that allows users to access videos, television shows and films digitally on request. These multimedia are accessed without a traditional video playback device and a typical static broadcasting ...

(movies, news clips) 3G-324M is agnostic to the actual

network that uses it. It can run as easily over

UMTS The Universal Mobile Telecommunications System (UMTS) is a 3G mobile cellular system for networks based on the GSM standard. UMTS uses Wideband Code Division Multiple Access, wideband code-division multiple access (W-CDMA) radio access technolog ...

as well as

TD-SCDMA The Universal Mobile Telecommunications System (UMTS) is a 3G mobile cellular system for networks based on the GSM standard. UMTS uses wideband code-division multiple access (W-CDMA) radio access technology to offer greater spectral efficiency ...

networks. 3G-324M operating over a circuit switched channel between two communication peers guarantees the fixed-delay quality of service for multimedia communications. Combining

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 The Adaptive Multi-Rate (AMR, AMR-NB or GSM-AMR) audio codec is an audio compression format optimized for speech coding. AMR is a multi-rate narrowband speech codec that encodes narrowband (200–3400 Hz) signals at variable bit rates rangi ...

, mandatory *

AMR-WB Adaptive Multi-Rate Wideband (AMR-WB) is a patented Wideband audio, wideband speech coding, speech audio coding standard developed based on Adaptive Multi-Rate audio codec, Adaptive Multi-Rate encoding, using a similar methodology to algebraic cod ...

(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 MPEG-4 Part 2, MPEG-4 Visual (formally International Organization for Standardization, ISO/International Electrotechnical Commission, IEC 14496-2) is a video encoding specification designed by the Moving Picture Experts Group (MPEG). It belongs to ...

simple profile 1 level 0, optional * ITU-T H.264, optional

References

External links

3GPP TS 26.111 - Codec for circuit switched multimedia telephony service; Modifications to H.324

IMTC 3G-324M AG
- Interoperability and testing activity group covering the 3G-324M and H.324 protocol * - An interesting article on the integration of 3G-324M into a Windows Mobile operating system
Understanding the 3G-324M Spec
{{Webarchive, url=https://web.archive.org/web/20080517183539/http://www.commsdesign.com/design_corner/OEG20030121S0009 , date=2008-05-17 - A good explanation on the specification of 3G-324M Videotelephony Application layer protocols