Of course, the ultimate end game of BT's broadband drive is FTTP (Fiber to the Premise). Leveraging a GPON-based network with 2.5 Gbps capabilities, BT estimates it will be able to deliver 100 Mbps downstream with a variety of tiered upstream speeds. From a theoretical perspective, the upstream could burst to 1.2 Gbps.
Long a holdout on FTTP, BT's initial mixed economy plan would include in addition to VDSL-based FTTC (Fiber to the Curb), 10 percent FTTP in both Brownfield and Greenfield deployment scenarios. In 2009, BT conducted two different trials: one in Roswell Hill and another in Wit Church, which is on the outskirts in Westchester in South Wales.
These FTTP deployments "were reasonable-sized trials totaling about 30,000 customers," Whitley said. "That was our first field trial and customer deployment process. Those went well and we should be passed by a million and a half homes this year and four million by the end of this year."
More recently, BT said it would increase its FTTX footprint from 40 percent to 66 percent of homes. While BT will continue to evaluate each deployment situation for each medium, the service provider sees the long-term opportunity for FTTP.
And while installing FTTP takes a detailed look at various aspects, including economics and duct availability, Whitley is optimistic about what they have accomplished thus far.
"We're pleased with our progress and we think that the mix between FTTP and FTTC is liable to change," he said. "We're trying where we can do FTTP even in a Brownfield area. When we do the detailed surveys, duct availability and overhead plant availability where we get the FTTP we will deploy it."
There are of course differences between Brownfield and Greenfield FTTP deployments. Greenfield deployments are typically are done in new housing or business developments that don't have any existing telecom infrastructure in place and can add fiber to the homes right from the beginning. Brownfield, however, means that there's existing outside plant network (aerial telephone lines) infrastructure in place, but that they have install an ONT and bring the fiber to the side of the home.
However, what's made the Brownfield deployments, many of which go through aerial cable connections, have been assisted through new innovations including blown fiber aerial cable.
"There's such a diversity of operational plant that's evolved over decades and there's no secret sauce yet," Whitley said. "We're taking all of the innovative technology methods we can see and using the best we can, which is why in the 12 months we have been going with the program we've been able to move from 10 percent to 25 percent of FTTP."
Still, even with all of its learning the dominant challenge with going to FTTP is gaining volume deployment over FTTC. BT currently has over 5,600 COs and 90,000 RT cabinets that connect UK customer premises.
While bringing FTTC "to the whole country means you're talking about going to 90,000 locations, but if you talk about FTTP you're going to north of 25 million premises," Whitley said. "There's a big big uplift engineering challenges associated with that."