EMC today will unveil its long-awaited cloud storage offering, a combination of hardware and software that promises to help businesses build and deliver Internet-based applications on a massive scale.

Code-named "Maui" and now known as "Atmos," the software portion is designed to manage petabytes of information across tens or hundreds of geographic locations, says Mike Feinberg, senior vice president of EMC's cloud infrastructure group. The offering is initially targeted at media and entertainment companies, telecoms, and Web 2.0 and Internet providers.

The Atmos software can either be purchased by itself and run on x86 servers virtualized with VMware's hypervisor, or it can be purchased in a bundle with EMC's "Hulk" hardware offering, which combines x86 servers with high-capacity, low-cost SATA drives. (Compare storage products.) Maui and Hulk have been the source of media speculation for months but EMC is only now revealing details.

Atmos can be thought of as storage virtualization at a massive scale. But "it's a lot more than that," says IDC analyst Benjamin Woo. In addition to enabling systems distributed around the globe, Atmos distinguishes itself with an object-based approach that makes information more useful and searches more relevant, Woo says.

"The Atmos announcement provides EMC with what I consider the next generation of storage systems," Woo says, noting that he expects similar announcements from competitors such as HP and Sun. "This allows customers to derive more value from the information they keep."

Rather than delivering storage in blocks, Atmos uses objects with user-defined metadata, making it easier to search for and retrieve information. This ability is crucial in legal discovery and other regulatory contexts, Woo says.

Atmos also provides policy-based data management capabilities determining how information is distributed and handled. "For example, information that is current and valuable may be defined as 'premium' and therefore require more copies in more locations than information that is older and accessed less frequently," EMC explains. "The older information may be compressed and retained with fewer copies in fewer locations."

Atmos also includes Web service APIs with REST and SOAP interfaces; auto-managing and auto-healing features that reduce administration time along with browser-based administrator tools that allow storage to be managed from any location; and multi-tenant support allowing applications and their data to be securely partitioned while being served from the same storage infrastructure. Additional features include replication, versioning, compression, de-duplication and power-saving disk drive spin-down.