stageleft

WARNING: Total nerdy post ahead based on my limited knowledge of a complex issue

For you San Diego Time Warner Cable (TWC) customers, you may have recently noticed the new program guide on your cable boxes/DVRs. Dubbed Navigator, it is basically Time Warner’s in-house cable box software, which allows them to replace existing licensed software from either Scientific Atlantic (SARA) or Aptiv Digital (Passport). More importantly, it signifies TWC’s move to their switched digital video (SDV) platform.

SDV basically reclaims massive amounts of cable bandwidth by only sending out requested channels. Traditionally, all channels are transmitted over cable lines, regardless of what channel you watch or subscribe to. So, even though you are watching 1 channel, the cable company is still broadcasting numerous unwatched channels, wasting precious bandwidth. This distribution method is the primary technical reason why Time Warner Cable’s HD offerings have been limited and their HD signal quality suspect. The lack of available bandwidth restricts TWC from adding new HD channels. Ever notice your picture turning into a giant mosaic of little blocks momentarily, especially in fast moving scenes? Known as macroblocking, this is a result of cable companies compressing bandwidth-hungry HD streams over their already saturated cable network. With SDV, Time Warner can reclaim large amounts of bandwidth by not broadcasting unwatched channels, thus allowing them to add more HD content and increase bandwidth for existing HD content. Navigator is the software piece that makes this happen.

The largest and most damaging drawback/side effect from the move to SDV is the effect on people who do not use Time Warner supplied hardware. People using CableCARDs in their TVs and 3rd party devices such as a Tivo S3 and TivoHD are SOL for the channels that are distributed using SDV. The hardware, namely CableCARD, and obviously the software will not support SDV. From what I understand, only digital tier channels are slated to be distributed over SDV, namely existing/new HD and seldom watched digital channels. When those channels switch over to SDV distribution, affected customers will not be able to receive those channels, in addition to already not having access to services such as Video-On-Demand (VOD) and Pay-Per-View (PPV). Digital broadcast channels such as CBS, NBC, ABC, and Fox should be unaffected since those channels are required by the FCC to be universally available. Plans to release a special SDV dongle to allow the necessary 2-way communication back to the distribution hub is in the works for Tivo owners and is planned to be released in the 2nd half of this year.

The root of the complicated problem is a mix of issues. Some of these include:

• Cable companies’ move to SDV in order to free up existing bandwidth without having to invest hundreds of millions of dollars in upgrading existing and adding new distribution infrastructure
• Poor, slow adoption and implementation of CableCARDs by cable companies and CableLabs
• Idiotic bickering and bureaucracy between CableLabs, cable companies, and the FCC in developing and enforcing open and standard protocols for 2-way cable communication and distribution

So far, Navigator has been pretty good. It is a tad bit slower than the previous running software (Passport) on my SA8300HD. The biggest improvement is that the sidebars on SD content is now black, instead of grey. I can also see how much remaining space is left on the hard drive for my recordings. Once the SDV transition is complete, we’ll see if TWC starts to rapidly add the dozens of HD channels already available to satellite customers.