Accelerating plans for a national wireless network, Comcast Corp. expects to light up eight million WiFi hotspots in the United States by the end of 2014, the company said Wednesday.

That would be eight times the one million hotspots the cable giant had deployed in early April in 39 states and Washington.

Comcast's "Xfinity WiFi Initiative" utilizes free wireless spectrum and wireless radios or gateways in outdoor areas such as parks and train platforms, as well as restaurants, stores, doctors' offices, and homes.

Sam Schwartz, chief business development officer for Comcast's cable division, said public Internet traffic is "completely segregated" from private Internet traffic and poses no security issues for its Xfinity subscribers in their homes. Access to the WiFi network is only available to Xfinity customers.

"In many places you go now, you will no longer need to spend money on cellular data," Schwartz said.

Comcast says the WiFi network won't be an expensive capital investment because of piggybacking on the wireless gateways in subscriber homes and hanging WiFi wireless transmitters on cable lines, tapping into the electricity and the Internet broadband already coursing through those overhead cable lines.

Comcast landed on the WiFi strategy because of the soaring demand for wireless bandwidth from tablets and phones, combined with the popularity of "TV Everywhere" applications that stream TV shows and movies to portable electronic devices.

Neil Smit, Comcast's cable division president, recently told Wall Street analysts that 75 percent to 80 percent of mobile data consumption takes place in homes and offices, areas served by WiFi.

Cisco Systems Inc., the telecom equipment-maker, says that 88 percent of U.S. data traffic on mobile and portable devices will travel over WiFi systems by 2018.

Comcast, meanwhile, said Wednesday that about 200 million out-of-home WiFi sessions have been initiated on its Xfinity network in the first four months of this year, a 700 percent boost from the same period last year.

Comcast observers have speculated on Comcast's WiFi network and what it could mean for the company - speculation the company hasn't dampened.

"We are in a position to think about where wireless is going and how we can participate in a way to build value and whether that is through our existing products or it's a new product," Comcast chief executive Brian Roberts said in a conference call with Wall Street analysts on April 22.

Comcast says it will add hotspots in Philadelphia, Atlanta, Baltimore, Boston, Chicago, Denver, Detroit, Hartford, Houston, Indianapolis, Miami, Minneapolis, Nashville, Pittsburgh, Portland, Sacramento, Salt Lake City, San Francisco, Seattle and Washington.