Foster City, Calif. -- Equinix, a Foster City-based provider of data centers and Internet exchange services, said that it plans to spend up to $55 million to further expand its Ashburn operations. The company, which last expanded in DC two years ago, said that strong market demand and financial returns have prompted it to build out an existing structure on its recently acquired Dulles corridor campus. Equinix said that the move will add 1,500-1,700 cabinets adjacent to its existing Internet Business Exchange (IBX) center. The company's IBX centers, which currently operate in 11 markets, allow customers to directly interconnect with every major global network and ISP for their peering, transit and traffic exchange requirements. The new facility is expected to open in early 2007.