Fans of HBO shows such as the 'Sopranos' and 'The Wire' can now watch them online if they are Comcast Corp subscribers, in the latest move by the cable TV industry to make TV programs available on the Web.

Both Comcast and HBO parent Time Warner Inc are leading the U.S. TV industry with initiatives called On Demand Online and TV Everywhere designed to help cable and satellite TV providers authenticate paying subscribers who choose to watch shows on the Web.

The companies said on Monday that a total of 750 hours a month of programing from the HBO and Cinemax brands will initially be available on Comcast sites, Comcast.net and Fancast.com and will grow over time.

Comcast On Demand Online programing already includes programing from Time Warner's Turner networks TNT and TBS. The cable company struck a deal with Liberty Media Corp's Starz last week.

By offering cable shows over the Web only to paying subscribers, the cable industry is trying to preempt the erosion of its lucrative mutually beneficial business model by distributing shows over the Web.

Consumers are getting used to TV shows being available for free online at sites like Hulu.com, a service owned by News Corp, NBC Universal and Walt Disney Co.

Cable program makers such as Time Warner make money by being paid by operators and sharing in advertising revenue. Meanwhile, cable operators rely on having programing to attract paying subscribers.

All sides are concerned that, if the industry does not start to be more flexible with its distribution model, cable shows will become widely pirated as has happened with other sectors such as the music industry.

(Reporting by Yinka Adegoke; editing by Andre Grenon)