The common wisdom is that the telephone companies are moving from copper to an all- or mostly fiber architecture while cable competitors will go to war with a hybrid fiber-coax mix buttressed by the latest iteration of the Data Over Cable Service Interface Specification (DOCSIS) standard.
That's neat and clean and, for the most part, accurate. However, it also appears to be on the point of shifting, at least to some degree. Increasingly, according to this Cable Digital News piece, cable operators are employing more fiber-rich approaches. The piece says there are two main ones: Fiber deep initiatives, as the name implies, deliver fiber further into the cable system than in the past. Operators also are showing interest in fiber-to-the-premises (FTTP) approaches, mostly in new build scenarios.
Gradually increasing the level of fiber in the cable plant is a tricky business from the technical and no doubt political points of view. The Society of Cable Telecommunications Engineers (SCTE), the cable group that officially promotes standards via its accreditation with the American National Standards Institute (ANSI), has established a subcommittee to work on the issues of enfranchising fiber. This 3wan.net post says that the main thrust is a technique called RF over Glass (RFoG), which is also known as Cable PON.
The idea, the writer says, is to square the circle by simultaneously promoting the use of more fiber while supporting the current HFC architecture and introducing nothing that will create problems for DOCSIS 3.0, the next version of the family of protocols the cable industry uses for transmitting data on cable plants.
The CDN piece says Aurora Networks and CommScope are two of the main suppliers of fiber to cable operators. More detail on Aurora is available in this Cable360.net item describing the vendor's appearance at the 2008 Cable Show this week in New Orleans. The piece says Aurora's GEPON platform enables selective migration from HFC to FTTP architectures. The firm also offers LcWDM, a wavelength division multiplexing (WDM) technology that supports eight downstream and 24 upstream transmission paths on a single piece of fiber.
Much of the tension during the next few years will focus on whether cable operators are getting enough capacity out of HFC-based DOCSIS 3.0 approaches. The bottom line, of course, is that the industry will only opt to move dramatically away from its roots if it becomes a competitive necessity.