Fog Lifting on RFOG
Cable's evolution toward a fiber-to-the-premises (FTTP) architecture, particularly in "greenfield" situations, took a formal step forward recently after the Society of Cable Telecommunications Engineers (SCTE) officially launched a standards effort around the "RF over Glass" (RFOG) project.
The SCTE Engineering Committee approved the RFOG program last fall. The task of crafting the standards has since been handed over to the SCTE Interface Practices Subcommittee. That work got underway in mid-March at SCTE's Exton, Pa., headquarters. (See SCTE Moves on RFOG.)
Development of RFOG will center on a wide range of interfaces that enable new FTTP networks to interconnect with the cable operator's hybrid fiber/coax (HFC) plant and headend environments Some of the RFOG project will involve specifications for elements such as passive splitters and directional couplers, gateway RF levels, gateway environmental requirements, and fiber-optic passive filters.
The standards resulting from RFOG will also aim to ensure that traditional digital set-tops and Docsis modems can run on FTTP plant managed by cable operators.
Real estate developers are pushing service providers for fiber connections, believing the advanced architecture could boost new-home prices. Some developers even appear to be willing to subsidize some of the additive costs a cable operator might be hit with.
The industry's cable FTTP effort has drawn significant interest (and even some new product lines) from a swath of equipment suppliers, including Cisco Systems Inc. (Nasdaq: CSCO), Motorola Inc. (NYSE: MOT), Calix Networks Inc. (NYSE: CALX), CommScope Inc. , Aurora Networks Inc. , Wave7 Optics Inc. , Alloptic Inc. , and Arris Group Inc. (Nasdaq: ARRS). (See SA Pitches Cable PON, Calix Uses RFOG, Moto Expands 'CablePON' Strategy, and CommScope Sees BrightPath for Cable FTTP.)
It's too early to predict when SCTE will finalize the RFOG standards, but it's clear that plenty of work remains ahead. "I don't know what kind of schedule will result, although I would not expect standards momentarily," SCTE VP of standards Stephen Oksala writes in an email response to Cable Digital News. "It depends on two factors – the speed with which people are willing to set pen to paper, and the degree to which the working group agrees with the details of what gets written down."
Although SCTE has yet to develop those standards, some MSOs, including CableOne and Bresnan Communications LLC , have already begun to deploy or test RFOG-like architectures in the lab or in greenfield developments. Time Warner Cable Inc. (NYSE: TWC) has not disclosed any RFOG projects but is said to be among the most interested MSOs.
Still, most view RFOG as an evolutionary path for cable operators.
"We believe, ultimately, that we'll see glass to every house," says Dave Pangrac, CEO of Pangrac & Associates Development Inc., which licenses FTTP tap, NIU, node, and laser technology to some traditional cable vendors that are going after the RFOG segment. "But [cable operators] won't rip out 4,000 to 5,000 miles of HFC plant to put in fiber."
"It's taking shape and we see demand for this type of product... but it's still the very early days in terms of the number of units that are deployed," says John Dahlquist, vice president of marketing for Aurora Networks, which supplies nodes and transmission gear to cable operators.
As for SCTE's involvement in RFOG, some vendors are concerned that developing far-reaching standards too soon could stifle product innovation.
"What's outlined [by SCTE] is a good starting point," Dahlquist says. "By coming up with standards too quickly, you end up putting everyone in one direction and the benefit of getting work going down on one path, but is it the right path?"
As for RFOG's next steps, "Working Group 5 (fiber optic) in our Interface Practices Subcommittee will be developing whatever specifications they think are appropriate," Oskala writes. "There is also an overall architecture specification that will guide them, although that will likely change over time as people get into the details."
— Jeff Baumgartner, Site Editor, Cable Digital News