With Google Fiber preparing an expansion into Charlotte, North Carolina, incumbent cable operator Time Warner Cable is trying to hold onto customers by dramatically increasing Internet speeds at no extra charge.

"The Internet transformation will begin this summer and will include speed increases on TWC residential Internet plans at no additional cost, with customers experiencing increases up to six times faster, depending on their current level of Internet service," Time Warner Cable announced last week. "For example, customers who subscribe to Standard, formerly up to 15Mbps, will now receive up to 50Mbps, customers who subscribe to Extreme, formerly up to 30Mbps, will now receive up to 200Mbps; and customers who subscribe to Ultimate, formerly up to 50Mbps, will receive up to 300Mbps, at no extra charge."

Google announced plans to enter Charlotte and a few other metro areas in January and is working with local officials to finalize the network design so that construction can begin.

TWC also announced improvements to its TV service, including 1TB of storage for recorded programs, double the previous amount.

Last year in Austin, Texas, Time Warner Cable upgraded its 100Mbps Internet plan to 300Mbps after Google decided to offer service there.

TWC's "Ultimate" Internet starts at $65 a month and has 50Mbps download speeds and 5Mbps upload. TWC did not say what it will boost upload speeds to. Google Fiber costs $70 per month for gigabit speed (1000Mbps) both upstream and downstream.

TWC is not the only company to boost service in order to fend off a challenge from Google Fiber. "Most of us live in monopoly, or at best duopoly, territory for broadband providers," Consumerist wrote Friday. "But when Google announces plans to expand into a new market, competitors either strive to dive in first, like Comcast in Atlanta, or drop prices to match, like AT&T in Austin and Kansas City."

But it's a different story in cities where incumbents don't have to match Google's $70-per-month pricing. In Cupertino, California, where AT&T just launched gigabit fiber but doesn't have to compete against Google, the service costs $110 a month.