We get this question often, so I thought I'd proactively post this answer.
The quick answer is: No. TelePresence does not require a dedicated bandwidth. As you may have heard, Cisco is a networking company :-) Cisco specializes in managing dynamic, real-time applications like voice and video and run these within the network, not on top of it. When TelePresence calls aren't active, this bandwidth can be devoted to other enterprise applications. When TelePresence calls are made, quality of service and bandwidth reservation capabilities in the network allocate the bandwidth needed.
So how much bandwidth do you need. That depends on the resolution (720p or 1080p) being used. Generally, between 2 and 3 Mbps per screen is used.
I welcome any questions. If you are a customer and can share your first-hand experience with this then that would be great.
Anthony
Cisco TelePresence Marketing Manager