In this photo released by HBO, from left, Kevin Connoly, Kevin Dillon, Adrian Grenier and Jerry... 
(AP)
You'll be able to watch popular cable television series such as HBO's "Entourage" and AMC's "Mad Men" on your computer by the end of the year without paying extra — as long as you're a Comcast Corp. subscriber watching at home.
Comcast will be the first cable TV operator to unlock online access to a slate of valuable cable shows and movies, aiming to replicate what's available on television through video on demand.
Time Warner Cable Inc. and others plan to follow as the pay-TV companies look to satisfy growing consumer appetite for online video while preserving subscription revenue.
Access will be carefully guarded: Comcast subscribers can initially watch shows and movies only on their home computers after being verified by the cable system. And for now, the online viewing will be restricted to those who also get Internet service through Comcast, not through competitors like phone companies.
Comcast, wanting to make sure the shows will remain off-limits to non-subscribers, still is working on providing access over competing home broadband systems as well as on the go — at work, on laptops and, one day, over cell phones.
At a briefing at Comcast's Philadelphia headquarters this week, executives said cable networks such as HBO will decide how much to put online. Some will include the current season's episodes only, while others could include archives of past seasons.
The offerings expand on what cable networks now make available online. Broadcast networks have been running full episodes of many shows for free on sites like Hulu, but cable networks have typically resisted. AMC's Web site, for instance, has the season premiere of "Mad Men" in its entirety but only video summaries of subsequent episodes.
Comcast's national rollout of "On Demand Online" — the company promises to replace that with a hipper, more contemporary moniker — comes months after the cable operator announced partnerships with 24 cable TV networks and broadcasters.
