Google today confirmed reports that it is building an undersea fiber optic cable that will link the U.S. and Japan for $300 million. (See Google's Building Unity Underseas.)

With today's announcement, it appears the Internet giant's appetite for infrastructure investments is growing. Google's infrastructure interests range from dark fiber to municipal WiFi to 700 MHz spectrum. (See Google's Balloon Dreams, 2007 Top Ten: Googly Moments, Google: Dark Fiber Story Not So Dark , Google's Own Private Internet, Google Pledges $4.6B for Spectrum, Google Takes WiFi Plan to the 'Hood, and Google's Powerline Play.)

Now, Google has joined a six-company consortium to construct a transpacific 10,000-kilometer linear cable system, called Unity. Other consortium members include Global Transit, Bharti Airtel Ltd. (Mumbai: BHARTIARTL), KDDI Corp. , Pacnet , and Singapore Telecommunications Ltd. (SingTel) (OTC: SGTJY).

The Unity system will have the potential to add up to 7.68 Tbit/s of bandwidth across the Pacific. Initially, the new cable system will boost transpacific lit cable capacity by about 20 percent. The first capacity will be available in the first quarter of 2010.

For Google, the new cable will provide access to capacity at build-cost and allow the Internet company to peer directly with ISPs in Asia.

NEC Corp. (Tokyo: 6701) and Tyco Telecommunications were awarded the contracts to construct and install the system, and construction is scheduled to begin immediately.

The new cable will connect Chikura, which is off the Japanese coast near Tokyo, and Los Angeles, as well as other U.S. West Coast points of presence. Unity will also be connected to other Asian cable systems at Chikura.

According to TeleGeography Inc. 's 2007 Global Bandwidth Report, bandwidth demand across the Pacific has grown at a compound annual growth rate (CAGR) of 63.7 percent between 2002 and 2007. The research firm estimates that demand for capacity will roughly double every two years for the next five years.

The consortium claims that the Unity cable system will be able to offer more capacity at lower unit costs by having a high fiber count. The cable system will have five fiber pairs and can be expanded up to eight fiber pairs, with each fiber pair having a capacity of up to 960 Gbit/s.

— Michelle Donegan, European Editor, Light Reading