While nobody wants to talk about it on the record, turning up HD voice for residential customers over the existing cable infrastructure is not simple. Issue stem from legacy equipment in existing networks, compatibility issues between IP phones and even between manufacturer implementations using the same chipset.
The biggest issue is working with existing PacketCable 1.5 and 2.0 spec equipment, with bugs cropping up all over the place between switches, so-called “wideband” SLICs, deployed CPE at homes and handsets. Older equipment not using SIP natively or implementing less mature/less tested SIP support can quickly run into issues when combine with newer up-to-spec/rev. equipment.
One of the more interesting tidbits heard during today’s discussions: One specific manufacturer’s chipsets delivering higher MOS scores using narrowband codecs than HD voice codecs when talking to the same implementation/phone.
Deploying HD voice for businesses in a hosted environment appears to be less of an issue since the hardware used to deliver services to businesses tends to be newer and more “tested” with existing standards. When offering business hosted services, MSOs are offering a more limited selection of customer equipment to choose from, typically with Polycom and/or Cisco handsets, so there are less “unknown unknowns” that crop up.
Despite it all, Comcast is apparently plodding along towards wider HD voice deployments. The company reportedly released formal HD voice specs to vendors around two months ago; it isn’t clear if this was for residential and business services.