Comcast Corp. (Nasdaq: CMCSA, CMCSK) has picked its hometown of Philadelphia as one of the first markets in which the MSO will deploy switched digital video (SDV), with Motorola Inc. (NYSE: MOT) serving as a lead vendor, Light Reading Cable has learned.

Comcast declined to comment on its current SDV deployment plans, but multiple industry sources say Philly is set to be among the first, if not the first, market to get the full SDV treatment from the operator, which had mothballed its earlier SDV activities in favor of an aggressive analog reclamation project. (See Comcast's $1B Bandwidth Plan .)

It's expected that Comcast will leverage SDV for its bandwidth-saving properties, but it could also give the operator an efficient distribution option for 3DTV, a programming category that will likely apply to only a small portion of cable subs for years. By using SDV instead of broadcast, Comcast would only send a multicast stream of a 3DTV channel when a customer in a given service group selected it for viewing. SDV could also set the table for a broader migration to an IPTV architecture. (See Comcast Forges 'Excalibur' for IPTV and SDV: Cable's Stepping Stone to IP Video? )

Although Comcast isn't revealing its specific rollout plans, the MSO has signaled its intention to get much more active with SDV and use it to clear up enough room to offer more than 150 HD channels. In June, the MSO mentioned in a Federal Communications Commission (FCC) filing that it planned to start deploying the technology later this year in a "limited number of systems, and more broadly in 2011-2012." (See Comcast Getting Ready to Uncork SDV.)

Time Warner Cable Inc. (NYSE: TWC), Charter Communications Inc. , and Cablevision Systems Corp. (NYSE: CVC) have been among the most aggressive with SDV so far, but Comcast isn't a complete stranger to the technology, either, having previously conducted tests in Denver; Cherry Hill, N.J., and in Minneapolis/St. Paul, Minn. (See Comcast Reveals SDV Test Beds and Comcast Expands SDV Test Pool.)

Motorola's complete role with the Philly deployment isn't yet known, but the vendor makes various pieces of the SDV ecosystem, including the control plane, session and resource managers, edge QAMs, and the SDV client that goes in the digital set-top.

But Moto won't be the only vendor to get in on Comcast's SDV action. It's also picked edge QAMs from Arris Group Inc. (Nasdaq: ARRS) and Harmonic Inc. (Nasdaq: HLIT), and has used SDV technology from Cisco Systems Inc. (Nasdaq: CSCO) in earlier trials. BigBand Networks Inc. (Nasdaq: BBND) is another approved SDV supplier at Comcast, but has yet to announce any deployment deals.

When Comcast decides when it will pull the SDV trigger in Philly, it'll have to give 30-day advance notice to the local franchise authority since it's considered a "change in service" in the eyes of the FCC. (See FCC Reverses SDV Ruling and FCC Dings TWC Over SDV .)

— Jeff Baumgartner, Site Editor, Light Reading Cable