The new service, now in a trial phase in 5,000 homes, will allow Comcast subscribers to watch favorite shows over the web with no additional charges.

On-Demand Online

To access the service, which Banse said will be called On Demand Online, subscribers will sign in online at Fancast.com or Comcast.net, get their identity authenticated as a Comcast subscriber, and then they will be able to watch cable shows online and on-demand shows over various devices.

At a subscriber's home, there is a one-time download for the player, and then up to three devices can be authenticated. Once authenticated, the laptop or other devices can be used anywhere.

The advertising model is still being worked out, with Banse describing the upcoming launch as "the first inning" of how the business will work.

"If you're an HBO subscriber, you'll be able to watch Entourage on your laptop," she said, referring to the hit HBO series. She added that the trial shows people like the video quality, the user interface, having access to content they watch on TV, and, in particular, being able to watch on-demand content.

Before Banse's comments, there had been speculation among industry observers that the service would only work if the user was on a Comcast broadband connection, which would have limited its appeal. There are reports that using the service at home will contribute to a user's monthly download limit.

'Absolutely Makes Sense'

Ross Rubin, director of industry analysis for consumer technology at the NPD Group, said that TV Everywhere -- "everywhere as long as you're a Comcast subscriber" -- is a reaction to the explosion of watching TV shows on the web, such as on Hulu.com.

Rubin noted that Hulu "has been aggressive about keeping its programming confined to the PC and off of TV." He referred to the trend among a number of major online video providers, such as Netflix and YouTube, to make their content available on TV sets through set-top boxes or electronics built into the TV.

By offering its cable channels to subscribers online, Rubin said, "Comcast can preserve its subscription revenue and add value to a subscription." This strategy "absolutely makes sense from a cable perspective," he added, and, for those who are already paying for a subscription, this kind of on-demand availability "is a nice bonus."

With the growing availability of TV shows and movies online, other major content owners are also moving to avoid losing control of their properties. For instance, Disney has developed its Keychest technology, which would allow consumers to pay one price to own a TV show or movie and then watch it from anywhere on any compatible device -- such as an iPhone, a computer's Web browser, or even an on-demand cable system . The program would live on a server and be accessed from those devices, and users wouldn't have to worry about storage .

A similar but potentially competing initiative, called the Digital Entertainment Content Ecosystem (DECE), is also developing a system. DECE's founding members include NBC Universal, Warner Bros., Microsoft , Lionsgate -- and Comcast.