With the Tuesday launch of its wireless Internet services in Portland, Ore.; Baltimore and Atlanta; US’ leading cable operator Comcast makes its mark as the first TV operator to roll out wireless broadband outside of Wi-Fi hotspots. The Comcast wireless service would make the surfing of the Web possible only on the laptops, not the other mobile devices.

Later this year, the company intends extending the wireless service to a few other cities, including Philadelphia, Chicago, Las Vegas, Honolulu, Texas, and Seattle.

Comcast is making a foray into the wireless broadband arena by packaging its current broadband products initially with Clearwire’s 4G wireless service. In some cities later on, the service will make use of the 3G network of Sprint Nextel Corp.

As compared to any of the other existing non-Wi-Fi services, the Comcast service – which expands its in-home broadband service together with a wireless Internet service, and offers speeds of up to 4 Megabits per second – will be much faster.

The service would allow consumers to sign up with either a plan wireless surfing plan applicable to their specific city, or a country-wide plan switching between 4G and Sprint's 3G network. The existing Comcast users can avail the new service with an additional $30 monthly payment to their already-in-use packages; with the nationwide access with 3G costing an additional $20 monthly charge.