America’s leading cable operator, Comcast, has announced plans to extend its fastest ‘wideband’ internet service to Oregon and southwest Washington state.

The wideband service is underpinned by a technology called DOCSIS 3.0, and allows for downstream connection speeds of up to 50-Mbps. It was first launched earlier this year in Minneapolis-St. Paul, and expanded to Boston, Philadelphia, southern New Hampshire, and parts of New Jersey, last month.

Comcast cable TV customers who sign up for the ‘Extreme 50′ broadband service are able to access the internet at download and upload speeds of 50- and 10-Mbps, respectively, at a cost of $139.95 per month. Those who use the ‘Ultra’ broadband offering get 22-Mbps downloads and 5-Mbps uploads, for $62.95 per month.

Comcast reportedly plans to extend its most advanced broadband services to “close to 10 million homes and businesses in the next couple of months,” covering most of the company’s 14.7 million subscribers.

But it doesn’t stop there. Even more advanced cable broadband services are in the works for the future, according to Comcast insiders.

“These speeds are only a preview of what’s to come — in the future we’ll have the capability to deliver even faster speeds in excess of 160 Mbps,” said the company’s senior vice president for Oregon and SW Washington, Curt Henninger.