The video stream is sent from the camera to an encoder-Cisco uses several from members of the Cisco Ecosystem Partner Program-for encoding at different bit rates. From there, the stream is sent to the Cisco External Media Hub, located at Cisco headquarters in San Jose, California (Figure 3). The Cisco External Media Hub comprises Windows Media and RealMedia streaming video servers and acts as the egress points for streams sent to external audience members. Rather than sending the stream directly to external audience members, which would unnecessarily increase traffic on the Cisco network, the Cisco External Media Hub sends the stream to a global Internet service provider, which then directs the stream to the viewer from the closest server
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