As operators scramble to optimize sufficient bandwidth with which to offer customers pipe-clogging video-on-demand service, a consideration that remains of vital importance is cost. A new piece of hardware developed in the laboratories at Scientific-Atlanta is poised to satisfy MSOs' need for speed while alleviating the ongoing cash crunch.

S-A last week announced the debut of its new coarse wave division multiplexing (CWDM) optical transport system, an add-on that expands the capacity of reverse path bandwidth by enabling each fiber in a hybrid-fiber coax network to support an eightfold increase in the number of wavelengths it can deliver.

Fleming Toft, GM of S-A Denmark, says that in contrast to traditional developments, which use between 32 and 64 separate wavelengths per fiber, the CWDM transport system uses only eight. This arrangement greatly reduces both cost and power, Toft says.

?Compared to traditional wavelength multiplexing, the CWDM is much cheaper,? Toft says. ?By mounting the CWDM directly into the optical nodes, operators will be able to deliver the reverse path bandwidth without having to worry about bottlenecks.?

Boosting the capacity of preexisting fiber helps to push fiber deeper toward customers. ?Instead of using one node to cover 500 subscribers, we can reduce that number to 100,? Toft says. ?The closer we can get the nodes to the consumer, the fewer consumers we have to serve with each node.?

The first CWDM system will be deployed next week in Europe. Toft says a major U.S. deployment will come following an evaluation of the system's European run.

A spokesperson for Time Warner Cable, which has deployed S-A hardware in three of its VOD markets, wouldn't comment on whether the MSO would install the optical transport hardware in its systems. ?Until we know more about it, I can't really say,? the rep said. ?Obviously, bandwidth is a concern, as is cost. But until we have more information, I can't speculate.?

S-A also heralded its latest hybrid management sublayer (HMS)-compliant transponder ? a monitoring device capable of measuring signal levels, performance, temperature and power consumption in its optical nodes ? as a means for operators to see a return on their investment. The transponder, a matchbook-size device consisting of a receiver, a small transmitter and a transistor, communicates with the head-end from its placement within the node, thus allowing operators an accurate picture of the node's operation at any given time.

?The transponder signals our movement toward an open standards environment in the cable world,? Toft says. ?Instead of being designed around proprietary standards, our equipment offers an interoperability that benefits the operator.?

The first three standards of HMS were produced and adopted by the Society of Cable Telecommunications Engineers in October 2001.

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