Comcast (NASDAQ: CMCSA) is beginning a 1 Gbps advanced trial for residential and business customers in Atlanta, laying a competitive challenge to Google Fiber (NASDAQ: GOOG) with its own similarly priced 1 Gbps service. But while the cable MSO is following Google's pricing scheme, it's not without a catch.

Eligible customers in Atlanta will be able to get the 1 Gbps data service for $70 a month only if they agree to sign a three-year contract or $139.95 a month without a contract.

After Comcast completes the advanced trial, the cable MSO said it plans to roll out the gigabit service at additional price points in other markets to gage consumer interest in gigabit speeds.

In Atlanta, Comcast will face off with Google Fiber, which will offer its standalone 1 Gbps symmetrical broadband service for $70 a month. Consumers will also have the option to purchase bundle of symmetrical gigabit fiber and TV for $130 a month. Finally, the dual tier is priced at $120 a month for many grandfathered users in Kansas City and Austin.

Interestingly, for the Atlanta launch Google Fiber replaced its "free" 5 Mbps offering -- one that required a one-time $300 installation fee -- with a 100 Mbps tier for $50 a month.

For its part, Comcast announced its plans to offer Gigabit Internet service using DOCSIS 3.1 technology in Atlanta and Nashville in early 2016, with Chicago, Detroit, and Miami to follow in the second half of the year.

Earlier, Comcast announced it had successfully installed its first DOCSIS 3.1 modem in Philadelphia, and one was installed in Atlanta a few days later. The service provider also offers Gigabit Pro, with symmetrical 2 Gbps speeds, to 18 million homes across the country.

Google Fiber isn't the only competitor that Comcast will face in the 1 Gbps race. Following Comcast's announcement in February to bring its 1 Gbps service to Atlanta and three other markets, AT&T (NYSE: T) said it was continuing to expand its offer of 1 Gbps services to select homes, apartments, and SMBs in to additional cities in the existing markets of Chicago, Dallas, Atlanta and Miami.

But the other question is what about business services? Google Fiber has mainly focused on residential services, but small to medium businesses (SMBs) are prime targets in Atlanta for 1 Gbps and fiber service that were traditionally only available to large businesses.

Although this initial 1 Gbps trial is focused on residential customers, Comcast plans to offer similar services to business customers over DOCSIS 3.1 at a later point.

Providing similar services to SMBs over DOCSIS 3.1 makes sense as it would enable Comcast to have a weapon to target telcos that are now going down market with fiber and Ethernet services. Now that cable has solidified its position in the SMB market, a number of telcos like AT&T are looking to lure or maybe win back smaller businesses.

For more:

- see the release

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