The delivery of video services is generally considered a critical and perhaps the most difficult problem that the Service Providers have to resolve in order to offer the "Triple-play" of video, data and voice. The transport of a mix of video, high-speed data and voice requires new solutions. For example, Gigabit Ethernet interfaces can offer better network economics when combined with a SONET or Fiber transport infrastructure. In this paper, we compare these transport technologies and present the results of a case study.The primary traffic, by volume, on the transport network will be IPTV video traffic from the head end to the access network. The number one priority for the transport network is to carry this IPTV traffic as efficiently as possible. Options to transport IP video include the following: Ethernet over SONET or ATM or Fiber. The choice will be influenced by different factors such as the embedded infrastructure, services mix, and traffic insertion at local COs for each service provider.The framework for the case study consists of the following: Network traffic model, technology options, and access network architecture/topology. The traffic model includes broadcast as well as unicast traffic based on subscriber density, take-rate and services per subscriber. We compare SONET drop-and-continue with Ethernet multicast technologies. The access network connects Regional Head-ends/Central-offices to Serving Area locations, which provide connectivity to end-users through remote DSLAMs with multicast capability.In this paper, we demonstrate that next-generation SONET, which provides capabilities for converged services (Ethernet and TDM) and a "drop and continue" feature, can offer efficient transport in terms of network economics and reliability. We also analyze the impact of new fiber deployment cost on the various technology options.

© 2006 Optical Society of America

PDF Article