DECEMBER 16, 2009 By Stephen Hardy -- Concerns about the bandwidth limitations of its Lightspeed fiber-to-the-node (FTTN) approach will lead AT&T to “quietly” evolve its optical access architecture, suggests Information Gatekeepers Inc. (IGI). The prediction comes within the 3Q09 edition of the market research and analysis firm’s High Speed Access Report.
AT&T has combined FTTH in greenfield applications with FTTN for brownfield use. The FTTN links see GPON-enabled fiber run to an average of 3000 ft (and some say as much as 5000 ft) from the carrier’s customers, after which existing copper cabling completes the connection. The two architectures support AT&T’s U-verse services.
The 3Q09 report cites “the latest ‘Rumor’” that AT&T is not seeing the bandwidth support from its FTTN infrastructure that it had anticipated. Rather than supplying 24 to 28 Mbps to each subscriber with fiber 2500 ft from the home, the FTTN links are providing 20 to 24 Mbps. The difference could prove significant, IGI suggests.
The potential shortcoming comes into relief as AT&T as the carrier determines what to do with the legacy fiber to the curb (FTTC) lines in the former BellSouth states of South Carolina and Georgia as it roles out U-verse. The FTTC architectures, in which fiber is placed closer to the customer than in FTTN, are more capable than AT&T’s preferred approach, IGI says in its report.
In response to questions from Lightwave, report author Clifford Holliday, president of B&C Consulting Services, says he believes AT&T will need to support at least 40 Mbps to the home within the next two or three years to keep U-verse services competitive. The only way to ensure support for such bandwidth will be to move fiber closer to the customer -- in the neighborhood of 2000 to 2500 ft in most cases. Such a move would enable support of up to 50 Mbps, he says.
Holliday sees such an evolution playing out in South Carolina and Georgia. AT&T will use the existing, deeper FTTC fiber as they upgrade the plant in those territories, then install the VDSL2 technology in use elsewhere for FTTN, he predicts. This combination, with fiber as close as 200 ft to the customer, will support at least 50 Mbps, Holliday says.
IGI’s High Speed Access Report subscription service includes not only the quarterly report on the xDSL, cable modem, and FTTX markets, but “FTTP Watch,” special reports as warranted, direct access to the report author, and “Customer’s Corner,” in which IGI answers subscribers’ questions.
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