Telco Stimulus Winners Favor GPON, But MSOs Prefer Other Fiber Options

South Texas-based VTX Telecom, a subsidiary of Valley Telephone Cooperative, is building a fiber-to-the-home (FTTH) network with approximately $88 million in stimulus loans and grants it was awarded. The telco selected Enablence Technologies to supply Gigabit Passive Optical Network (GPON) and point-to-point Active Ethernet for its more than 15,000 subscribers.

VTX is leveraging the Enablence platform to construct a fiber-based network throughout the southern region of Texas to support triple-play services to residential and business subscribers.

Up to this point, VTX’s service offering has been mixed. With 18 exchanges, it offers only voice service in some of its footprint while offering IPTV and Internet service along with voice in other areas.

Kevin Brown, vice president of marketing system/North America at Enablence, says the provider has chosen to deploy GPON to residences and point-to-point to businesses. "They were looking for a platform that could support both technologies," he says. "With stimulus money, they’re on a strict time frame; they have three years to complete."

As far as selecting GPON for the residential services, Brown notes telcos often favor GPON based on it being an ITU standard, while cable companies favor EPON and IEEE standards. "It’s more of a religious battle," he explains. (For more information, read "Telcos Pick GPON for Good Reasons").

Independent consultant Victor Blake agrees that telcos tend to prefer GPON because, from their point of view, they may believe it’s more of a proved technology because it stems from ITU standards. However, he adds it’s inaccurate to say that it’s a better choice for them than EPON. In addition, RF Over Glass (RFoG) can transmit video over FTTH, and it works with both EPON and GPON.

Blake, along with executives from Enablence, worked on the RFoG standard – SCTE IPS910; and work has just begun on SCTE IPS911, the next-generation RFoG standard.

"RFoG is a new standard for transmitting cable TV signals over FTTH," states an Enablence white paper HFC vs. FTTH. "It is seen as an interim step before cable operators switch to EPON. Enablence has RFoG technology and is actively selling it as a way to be there when the cable guys are ready to switch to the more efficient EPON – or GPON – technology."

Blake, however, doesn’t necessarily see RFoG as just an "interim step," saying "some operators are interested in RFoG because it has very effective long reach in rural areas. A lot of early adopters are using it for that."

He continues, "Other operators might use it as a way to get fiber to the home without buying into the PON technologies. This makes sense for video where the platforms (set-top boxes, etc.) may not be IP-ready and rely on RF transmission. However, for data services, RFoG really carries all of the cost of FTTH or FTTP with none of the benefits. Thus, it makes most sense as an overlay for EPON to offer video with existing (STB) platforms."

The Business Case

"It’s really the service providers’ business drivers versus what technologies you’re going to pick," says Enablence’s Brown.

Providers often have two internal groups: one focused on residential services and one for businesses. While telcos are scrambling to grab video market share, MSOs are making a drive for more business customers. (For more on this, read the upcoming March issue of Communications Technology magazine.)

For cable, typically the business services group doesn’t have as many subscribers compared to the residential group. According to Brown, "Supporting a lesser amount of customers is less disruptive on back office provisioning changes."

He says many cable operators appear to be waiting for DOCSIS Provisioning over Ethernet (DPoE), which will define a standard way to manage FTTH systems as if they were DOCSIS systems. It reportedly will help save the MSOs’ back-office investments.

Today, GPON offers downstream peak rates of 2.5 Gbps and upstream peak rates of 1.2 Gbps, while available EPON only has peak rates of 1 Gbps, symmetrical for downstream and upstream.

Brown anticipates that, toward the end of 2011 when DPoE is in place, some cable operators will introduce 10GE-PON, with increased EPON data rates, which he called "turbo-EPON."

As far as telcos like VTX, Brown says they’re on a time deadline to implement their stimulus awards. GPON, with its 2.5 Gbps downstream peak rates combined with Active 1 Gbps (symmetric) point-to-point, works fine for them.

-Linda Hardesty