By Xiaomei Liu, Alon Bernstein, Cisco Systems
DOCSIS 3.0 and Modular CMTS promise to provide ten times the bandwidth at one tenth of the cost, compared to existing CMTS technology. With these forward-looking trends, it is becoming increasingly viable to consider a channel-bonded DOCSIS network as a fullyconverged network to transport video, voice and data. A bonded, converged and asynchronous data pipe, married with variable bit rate (VBR) video coding, can deliver the full potential of IPTV over cable. This paper examines the technical and economic implications of VBR over DOCSIS. It proposes an IP-level VBR network statmux to deliver VBR video over channel-bonded DOCSIS and quantifies the efficiency of the network statmux with the results of lab tests. It provides insights into various architecture issues related to VBR delivery. Finally, it explores mechanisms to improve robustness and enhance the subscriber viewing experience.