It's a "ploy" aimed at small and midsize businesses (SMB) that won't likely appeal to large organizations, said Chris Foster, a storage analyst at Technology Business Research Inc. in Hampton, N.H. "Even if I'm an SMB, I don't know if I want to start storing stuff outside [my own network], particularly customer data."

Foster also noted that there are plenty of established vendors offering such services. "I'd rather go to someone whose core competency is managing or storing data," Foster said.

Ronald Schmelzer, an analyst at ZapThink LLC in Baltimore, said that Amazon is trying to position itself as a technology platform, rather than as just an e-commerce site. "It's a stretch of the business plan," Schmelzer said.

Amazon created its Web services division in July 2002 to encourage software developers to create and offer custom applications to Amazon.com sellers. The sellers then pay to use the applications, including specialized inventory and tracking software, to customize their online stores.

The unit has signed up more than 150,000 registered developers since its creation.