Cisco Cisco WebEx Meeting Center WBS30 Libro bianco

 

 

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All video resolutions listed in Table 4 are the default target resolutions. They are based on the assumption of a 

perfect network environment. In the video engine design, Cisco has implemented network adaptation to promote 

smooth transition from lower-quality to higher-quality video, and conversely. Between the default target resolutions, 

fps, and bandwidth (90p, 180p, 360p, and 720p), you can send and receive other temporary resolutions to allow 

graceful adaptation of the video quality to current conditions. 

One of the most common network problems is insufficient or unreliable bandwidth. Bandwidth limitation can cause 

packet loss, delays, and jitters. In addition, if the required sending and receiving bit rates exceed the bandwidth 

limitations of the network, network congestion will occur and eventually results in a poor video experience. During 

the video session, the client software closely monitors the transmission and packet-loss rates through the Real- 

Time Transport Control (RTCP) feedback protocol. When changes in network conditions are detected, the quality- 

of-service (QoS) module allocates bandwidths for a voice over IP (VoIP), data, and video session. The video 

session then adjusts the outgoing bit streams through encoder control. After the network condition becomes stable, 

the QoS module, together with the encoder control module, upgrades the video experience if the bandwidth allows 

it. This QoS prioritization is for the WebEx client software operation. 

The bandwidth bottleneck detection is a function to probe the current bandwidth capability by sending and 

receiving network test packets. The probing results are used to guide the network adaptation process as described 

in the previous section. In general, bandwidth bottleneck detection is at: 

● 

The start of a meeting 

● 

When the video start or stop button is pressed 

● 

Before upgrading video resolution to the next level that involves a significant bandwidth gap 

Cisco TelePresence

®

 integration with the Cisco WebEx Meeting Center web conferencing service can enable 

transparent voice, video, and data sharing between Cisco TelePresence environments and remote Cisco WebEx 

users. This integration extends the reach of a Cisco TelePresence meeting to remote participants. 

Figure 8 shows a picture of the participants list with a Cisco WebEx Enabled TelePresence meeting as viewed by 

the WebEx participant and meeting information screenshot.