IBM and EMC have finally come to an agreement on storage management and interoperability.

The IT giant and the market leader in high-end RAID have agreed to swap programming interfaces for their respective disk arrays.

The pair further agreed to extend existing cross-support initiatives to more of their respective storage devices, adding servers and software to the agreement.

Significantly, Big Blue has now licensed its proprietary APIs for the Shark array to EMC in order for the latter's flagship Symmetrix DMX to support IBM's Peer-to-Peer Remote Copy, Extended Remote Copy and FlashCopy software.

The deal, which is specific to mainframe environments, will enable users to replicate between Shark and DMX arrays.

Both companies had already swapped APIs with the other major vendors, Hewlett Packard and HDS, but this latest deal is the first between them.

Nigel Ghent, EMC's UK and Ireland marketing director, stressed that this deal is different in that the programming interfaces will not be proprietary, but based on the emerging SMI-S standard developed by the Storage Networking Industry Association.

The one-way licensing transaction for Shark APIs, which involved the payment of an undisclosed sum to IBM, is also unique to this deal because only IBM is still in mainframes.

The agreement was largely facilitated by EMC dropping its WideSky project for middleware to interface with other vendors' device management software.

Although EMC insisted that WideSky was not a proprietary play, other manufacturers remained suspicious, particularly IBM, which refrained from swaps until after its demise.

Hamish Macarthur, a director at storage analyst Macarthur Stroud, suggested that the deal was "part of the drift towards SMI" going on in the market.

"IBM has always tried to open things out, and now EMC is following that same line," he said.

"But [the real issue is] how will users react to, say, IBM telling them that it now supports storage from EMC, HP and so on?"

API swaps

IBM and HP - August 2002
IBM and HDS - March 2002
EMC and HP - July 2002
EMC and HDS - March 2003
IBM and EMC - October 2003