AT&T: G.hn holds promise of self-installed triple play

G.hn -- the versatile in-home networking standard being authored by the International Telecommunications Union (ITU) and promoted by the HomeGrid Forum – offers carriers the prospect of slashing operating costs by enabling self-installation of triple-play services, according to its proponents. But if it can overcome some of its inherent technological hurdles, it might also give service providers a greater role in home networking as a managed service, according to AT&T, which is helping to shape the standard.

“From a service provider’s perspective, one of the things I bring to the party -- that is new to a large degree for G.hn -- is the view that this is part of a managed service and not just a couple boxes in the home that have to talk to each other,” said Tom Starr, Lead Member of Technical Staff at AT&T Labs and a contributor to G.hn standards efforts. “In the past, the customer goes down to the local electronics retailer, buys some boxes and hooks them together. Now, as part of a service, the service provider becomes part of the equation, and we add value by making it a better experience for the customer.”

G.hn aims to unify management of a wide range of consumer devices (including TVs, DVRs, game consoles, PCs, phones, printers, home gateways, routers and optical network terminals) over a range of existing infrastructure (including coaxial cable, Cat 5, phone and power lines) by instituting a common interface between the network’s physical layer and its media access control (MAC/PHY). The technology could allow consumers to move content such as music or video from one device to the next, for example.

G.hn was given a push with last year’s creation of the HomeGrid Forum, whose members include AT&T and Qwest Communications as well as British Telecom, France Telecom, Japan’s NTT and China Telecom. The forum says the technology is now ready for chipset vendors to begin work on silicon designs and that the first G.hn nodes should hit the market in the first half of 2010. If that holds true, ABI Research said last year, some 42 million G.hn nodes could ship in 2013.

With a physical-layer performance target of 1 gigabit per second, G.hn supports speeds of 300 megabits per second over coaxial cable, 200 Mb/s over phone lines and Cat 5 cable and 100 Mb/s over power lines. However, high speeds are not a big driver of G.hn demand, Starr said in a recent Webcast. “It’s great [G.hn] supports higher bit rates. But that’s not what hurts today…The current generation of technologies can suffice.”

Instead, AT&T is looking at G.hn for increased coverage and versatility in the home as well as security, service quality and manageability. G.hn is designed to keep one-way inter-node latency below 2 milliseconds for VoIP and below 5 ms for IPTV. “That’s a challenging requirement, but from what I’m seeing, I think we’ll be able to meet these needs,” Starr said.

But the primary benefit of G.hn, Starr said, is the prospect of allowing customers to self-install a range of consumer electronics gear for bundled telecom services the way they self-install ADSL today.

“[With today’s ADSL installations], no technician ever goes to the home,” Starr said. “This is not going to be easy. But this is the ultimate goal we hope to achieve [with G.hn].”