ITU-T H.243-2005
使用1920Kbit/s以内的数字信道在3个或以上视听终端间用于建立通信的程序.研究组16
Procedures for establishing communication between three or more audiovisual terminals using digital channels up to 1920 kbit/s Study Group 16
ITU-T H.243-2005 发布历史
This Recommendation concerns the system operation for a conference call between three or more audiovisual terminals. It is applicable to a single MCU containing an audio mixer and a video switch according to the provisions of ITU-T Rec. H.231, to calls involving two such MCUs, and to calls involving three or more MCUs in a star configuration. It is also applicable to MCUs containing a video mixer. ITU-T Recs H.233 and H.234 address issues concerning the use of the Encryption Control Signal (ECS). ITU-T Rec. H.242 provides for communication between two audiovisual terminals connected point to point, using the frame structure defined in ITU-T Rec. H.221. ITU-T Rec. H.230 defines a number of Control and Indication signals, including those used in the multipoint communication procedures described in this Recommendation. Three or more audiovisual terminals may be put into communication to form a conference call, by means of one or more Multipoint Control Units (MCU). The general principles of multipoint communication are described in ITU-T Rec. H.231. The means by which digital channels are established between terminals and MCUs, and between MCUs, is outside the scope of this Recommendation (see ITU-T Rec. H.200/AV.420). It should be noted that the physical realization of an MCU may be such that two or more independent conferences may be set up within the same unit; logically, however, there is no relationship between these conferences; the text herein refers to an MCU only as a logical entity pertinent to the particular call of concern. This Recommendation concerns only the flow of signals along the fixed digital paths, which may be at 64 kbit/s (56 kbit/s in certain networks) or multiples thereof up to 1920 kbit/s. The flow consists of a multiplex of audio, video, control and indication signals, and optional user data as defined in ITU-T Rec. H.221 which must be handled by the MCU in a way which is satisfactory to the users. The signal multiplex on each path is fully in accordance with ITU-T Rec. H.221: the BAS commands define explicitly how the demultiplexer at the end of each link shall operate. Likewise, the basic procedures for initialization and mode switching are fully in accordance with those defined in ITU-T Rec. H.242 for point-to-point working. However, the composition of the multiplexed signal transmitted by each terminal and by the MCU is determined by terminal procedures and multipoint system procedures, as follows: a) Terminal procedures are defined in service-specific system Recommendations, such as ITU-T Rec. H.320 for visual telephony. b) Multipoint system procedures are defined in this Recommendation and are not of themselves service-specific. c) ITU-T Rec. T.120: by making use of the T series, MCU and terminal procedures may be greatly enhanced, offering far more sophisticated specific applications to the user. Such enhancement is outside the scope of this Recommendation, although interactions with specific T.120 methods are described here. For definitions of terms used in this Recommendation, see ITU-T Rec. H.231; for definitions of SBE and MBE symbols, see ITU-T Rec. H.230.
ITU-T H.243-2005由国际电信联盟 IX-ITU 发布于 2005。
ITU-T H.243-2005 在中国标准分类中归属于: M63 节目传输。
ITU-T H.243-2005 发布之时，引用了标准
- ISO 639-1-2002 语种名称代码.第1部分:α-2代码
- ISO/IEC 10646-2003 信息技术.通用多八位编码字符集(UCS)
- ITU-T G.711-1988 语音频率的脉冲编码调制(PCM)
- ITU-T G.722-1988 使用64 kbit/s内的7kHz音频编解码器的系统方面
- ITU-T G.728-1992 综合业务数字网(ISDN).电话终端的技术特性.第8部分:在16 kbit/s速率使用低时延码激励线
- ITU-T H.221-2004 音视用户终端业务中64到1920kbit/s通路的帧结构-H系列系统:视听服务系统的视听和多媒体系统
- ITU-T H.224-2005 采用视听电信业务中221kbit/s信道帧结构的LSD/HSD/MLP信道单工应用的实时控制协议-H
- ITU-T H.230-2004 音视系统中帧同步控制信号和指示信号-H系列系统:视听服务系统的视听和多媒体系统基础设施-系统方面
- ITU-T H.231-1997 使用高达1920kbit/s数字通道的视听系统多点控制单元-H系列:视听服务系统的视听和多媒体系统基础
- ITU-T H.233-2002 视听服务的可信性-H系列:视听服务系统的视听和多媒体系统基础设施-系统方面 研究组16
- ITU-T H.242-2004 使用2Mbit/s以内的数字信道在视听终端间建立通信的系统-H系列:视听服务系统基础设施-通信程序
- ITU-T H.261-1993 P×64kbit/s视听业务的视频编解码器-非电话信号线路传输 研究组15 28pp
- ITU-T H.262-2000 信息技术-移动图画和相关视频信息通用编码:视频H系列:视听服务系统和多媒体系统基础设施-移动音频编码
- ITU-T H.263-2005 视听服务系统低速通信视频编码-移动图画编码 研究组16
- ITU-T H.320-2004 窄带视频电话系统和终端设备 H系列:非电话信号传输-视听服务系统基础设施和终端设备 研究组16
ITU-T H.243-2005的历代版本如下：
- 2005年 ITU-T H.243-2005 使用1920Kbit/s以内的数字信道在3个或以上视听终端间用于建立通信的程序.研究组16
- 标准号
- ITU-T H.243-2005
- 发布日期
- 2005年
- 实施日期
- 废止日期
- 无
- 中国标准分类号
- M63
- 发布单位
- IX-ITU
- 引用标准
- ISO 639-1-2002 ISO/IEC 10646-2003 ITU-T G.711-1988 ITU-T G.722-1988 ITU-T G.728-1992 ITU-T H.221-2004 ITU-T H.224-2005 ITU-T H.230-2004 ITU-T H.231-1997 ITU-T H.233-2002 ITU-T H.242-2004 ITU-T H.261-1993 ITU-T H.262-2000 ITU-T H.263-2005 ITU-T H.320-2004
- 适用范围
- This Recommendation concerns the system operation for a conference call between three or more audiovisual terminals. It is applicable to a single MCU containing an audio mixer and a video switch according to the provisions of ITU-T Rec. H.231, to calls involving two such MCUs, and to calls involving three or more MCUs in a star configuration. It is also applicable to MCUs containing a video mixer. ITU-T Recs H.233 and H.234 address issues concerning the use of the Encryption Control Signal (ECS). ITU-T Rec. H.242 provides for communication between two audiovisual terminals connected point to point, using the frame structure defined in ITU-T Rec. H.221. ITU-T Rec. H.230 defines a number of Control and Indication signals, including those used in the multipoint communication procedures described in this Recommendation. Three or more audiovisual terminals may be put into communication to form a conference call, by means of one or more Multipoint Control Units (MCU). The general principles of multipoint communication are described in ITU-T Rec. H.231. The means by which digital channels are established between terminals and MCUs, and between MCUs, is outside the scope of this Recommendation (see ITU-T Rec. H.200/AV.420). It should be noted that the physical realization of an MCU may be such that two or more independent conferences may be set up within the same unit; logically, however, there is no relationship between these conferences; the text herein refers to an MCU only as a logical entity pertinent to the particular call of concern. This Recommendation concerns only the flow of signals along the fixed digital paths, which may be at 64 kbit/s (56 kbit/s in certain networks) or multiples thereof up to 1920 kbit/s. The flow consists of a multiplex of audio, video, control and indication signals, and optional user data as defined in ITU-T Rec. H.221 which must be handled by the MCU in a way which is satisfactory to the users. The signal multiplex on each path is fully in accordance with ITU-T Rec. H.221: the BAS commands define explicitly how the demultiplexer at the end of each link shall operate. Likewise, the basic procedures for initialization and mode switching are fully in accordance with those defined in ITU-T Rec. H.242 for point-to-point working. However, the composition of the multiplexed signal transmitted by each terminal and by the MCU is determined by terminal procedures and multipoint system procedures, as follows: a) Terminal procedures are defined in service-specific system Recommendations, such as ITU-T Rec. H.320 for visual telephony. b) Multipoint system procedures are defined in this Recommendation and are not of themselves service-specific. c) ITU-T Rec. T.120: by making use of the T series, MCU and terminal procedures may be greatly enhanced, offering far more sophisticated specific applications to the user. Such enhancement is outside the scope of this Recommendation, although interactions with specific T.120 methods are described here. For definitions of terms used in this Recommendation, see ITU-T Rec. H.231; for definitions of SBE and MBE symbols, see ITU-T Rec. H.230.