在分组交换网络中，用于视频会议系统的多媒体会话信令协议主要有H。323和SIP。

H. 323 and SIP are the main signaling protocols which control multi-media sessions in a multimedia conference system over the packet network.

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IMS允许运营商对多媒体会话进行适当收费：如果用户通过3 G移动网络使用了视频会议，则通常会产生包含音频和视频的大量数据传输。

IMS allows operators to charge multimedia session appropriately: If a user USES videoconference over the 3g cellular network, there is usually a large data transfer that consists of audio and video.

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在拨号广域网中设置较低的会话质量同样可以达到安全多媒体会议的通讯效果。

The system also provides secure communication on WAN if set comparably low session quality.

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