Cable's Digital Migration: Why It's Happening
As cable companies push to achieve an all-digital world, the analog versions of existing channels are fast disappearing on some cable systems. This is happening because the cable operators are aggressively seeking ways to free up bandwidth for high-definition broadcasts and for additional programming channels. They are also interested in finding more bandwidth for services such as games, voice communications, and interactivity. In the end, consumers will gain more access to digital services--and cable companies will have more services to offer to consumers.
It's not all bad news: Customers who have a single TV in their home, set up in a straightforward, traditional arrangement, might (depending on the service) even get a little more for their dollar in the switch to digital. But enthusiasts who have complicated entertainment setups--and people whose homes contain multiple TVs--will feel the pinch.
Cable companies are pursuing two main strategies for freeing up bandwidth. Whether you're affected by either of these depends on a mix of where you live and what company provides your cable.
The first approach involves eliminating the analog feed for cable channels. Cable companies that take this approach--Cablevision and Comcast--are doing so with channels that they are also broadcasting in a digital format.
Approach number two is termed switched digital video. In this situation, channels are on a system that includes a switch, so they only get piped into your house if your cable box requests them. The arrangement works similarly to the way video-on-demand does. Say you want channel 132: You request it using your remote, after which the cable company sends the signal to your cable box. Before companies instituted this switch system, all signals were continuously broadcast through the pipe, and all you had to do was tune in to the station you wanted.
Switched digital works only with a set-top box, however. If you use a CableCard--which some cable companies supply in place of a box, and which users can slip into newer TVs or digital video recorders (like TiVo's Series3 boxes)--you'll find that the card can't communicate back to the cable provider. As a result, you won't be able to record channels on the switch. The next generation of CableCard, which supports Tru2way, will correct this deficiency. Tru2way allows interactive communication between the card and the cable company; unfortunately, as yet it remalns a rarity.
Time Warner Cable has deployed switched digital in some markets; only two Time Warner markets--New York and Los Angeles--have gone all-digital (and even there, only in some areas). Cox Communications is using switched digital technology in Arizona, Northern Virginia, and Orange County, California, and it has plans to roll out the technology in other markets this year.
Next: Where Does Your Cable Company Stand?