September 1, 2010

Deploy Fiber Deep To Stay On Top

By Dawn Emms

How does cable maintain its position as king of the triple-play hill? Cable operators face growing competitive pressure from telcos and satellite TV in the delivery of video, voice and high-speed Internet access to consumers. To address the threats posed by the competition and to keep customers away from these rivals, cable is rolling out such sophisticated services as HDTV, digital voice and DOCSIS 3.0 high-speed data. And they are evolving their networks with such architectures as Fiber Deep to support these bandwidth-intensive offerings.

Pushing fiber deeper into the network allows cable operators to increase capacity, gaining as much as a 500-percent jump in downstream bandwidth and a 1,000-percent boost for upstream bandwidth. Fiber Deep achieves these increases without incurring significant capex when compared to the alternatives, while also keeping operating costs low. Taking aim at opex is especially critical in today’s competitive landscape. Fiber Deep eliminates some of these expenditures, reducing operational and maintenance costs within the network by as much as 65 percent.

And pushing fiber deeper into a cable network eliminates the need for RF amplifiers, which results in the removal of about 70 percent of network actives. Taking active components out of the network cuts power costs by as much as 50 percent, enabling cable operators to save money on energy costs and making Fiber Deep cable's first truly “green” network architecture.

Regarding energy costs, the savings are significant. Power delivered to a typical 70,000-home service area, and serving an average of 85 homes per node, can cost $75,000 annually with a Fiber Deep-supported network. That compares with $310,000 in power costs for a similar-sized HFC network serving 500 homes per node. In this scenario, Fiber Deep saves a cable operator $235,000 on annual energy bills.

“By pushing fiber deep into a network, cable operators also reduce the number of homes served per node...to typically fewer than 100.”

In terms of capex, Fiber Deep is more economical for a cable operator to deploy in urban and suburban markets. RF over Glass (RFoG) technology is cable-friendly because, like Fiber Deep, there's no need for drastic changes to headend infrastructure or a switch-out of set-top boxes or cable modems. However, RFoG is more expensive in medium- and high-density markets when compared with Fiber Deep.

In urban areas, an aerial-supported RFoG deployment could cost a cable operator nearly $100,000 per mile and as much as $150,000 per mile for an underground build. An aerial Fiber Deep deployment is roughly about a third of RFoG’s aerial costs and about $50,000-per-mile cheaper for an underground build. RFoG is a winner only in low-density, rural areas. In these markets, Fiber Deep tops $20,000 per mile for an aerial build and as much as $50,000 per mile for an underground deployment.

By pushing fiber deep into a network, operators also reduce the number of homes served per node, from an average of 500 to 2,000 in a traditional HFC network to typically fewer than 100.

Cable operators also can easily enhance and expand their installed Fiber Deep infrastructure to handle future demands. For example, a cable operator can drop a Node PON module into an installed Fiber Deep node to service a local business, to further build fiber throughout a service area or even to take fiber to the premises. This Node PON-supported approach increases network capacity, providing symmetrical 1 Gbps bandwidth upstream and downstream. And by strategically placing a PON OLT in the network, cablecos overcome distance limitations and can serve large numbers of subscribers from a single node.

And Fiber Deep is enabled by digital return, key for return-path issues associated with DOCSIS 3.0. As such, it provides a platform for future services that likely will require even higher QAM schemes.

Dawn Emms is director of marketing at Aurora Networks. Contact her at demms@aurora.com.