"RSA is able to offer EMC customers [assurance] that only authorized users have access to information," said Art Coviello, CEO and president of RSA. "It's time security becomes an integral part of the information [storage] infrastructure."

Upon completion of the acquisition, RSA will operate as EMC's information security division, with headquarters in Bedford. Art Coviello will become an executive vice president of EMC and president of the division.

Phil Shacter, an analyst at Midvale, Utah-based Burton Group, said it's hard to see the immediate driver for EMC's move. But over the longer term, RSA's technologies will allow the storage vendor to offer strong access control and auditing capabilities on top of its storage management products.

"EMC has this major role as custodian of important corporate data," Shacter said. Giving customers a better way to protect that data makes sense for EMC, he said.

RSA itself had been well positioned to grow, especially as a provider of strong authentication technologies, Shacter said. The whole notion of strong identity management and the interest in multifactor authentication -- in particular in the financial and health care communities -- had given RSA a "whole lot of traction" recently, he said. "There was a lot of upside in their end of the business. That helped give them a revenue stream that was healthy and probably improved their evaluation."