Apple has already signed a seven-year lease for extra data space with a new Silicon Valley data center built by DuPont Fabros Technology (DFT). It is rumored that the purpose is to launch a new set of online services under the name iCloud.

Apple runs its own data centers in Newark, California, and at its headquarters in Cupertino, California. The company will try new ways to expand its data space: using someone else's server room. The new center is under construction in Santa Clara, less than 10 miles from its headquarters.

Apple is leasing about 11,000 square feet of space from DFT, which is a major supplier of third-party server power to such clients as Yahoo (YHOO), Facebook and Google.

What’s the giant new data center for? The most possible guess is that Apple is preparing beta versions of iOS 5.0 and Mac OS X Lion involving the mysterious iCloud. The new technique will allow users to store and synchronize a wide range of data on Apple servers. Apple will unveil the future of iOS and Mac OS at a Worldwide Developers Conference next month.

Also, GigaOm reported that Apple has already purchased the domain for $4.5 million from Swedish outfit Xcerion last month.