Cisco has decided to stop selling re-branded versions of EMC's Celerra network-attached storage (NAS) products. These were being sold as part of Cisco's wide area file system (WAFS) product line.

This follows on from Cisco's investment in super-NAS start-up NeoPath. EMC is one of the top two NAS product sellers with its Celerra product line. It acquired Rainfinity last year, gaining technology to virtualise NAS products.

EMC chairman Joe Tucci recently said that Storage virtualisation could become a billion dollar business for EMC.

What has the NeoPath technology got that is superior to Rainfinity? The speculation is that Neopath's product could function as a blade or other embedded element in a Cisco storage networking switch. Cisco has no wish to sell storage as such; its aim is to sell products providing networked access to storage. EMC's developing InVista storage area network (SAN) virtualisation will run as software on a processing element in the Cisco MDS networked storage switch/director products in this way.

The implication is that the Rainfinity technology is not developing in the direction Cisco prefers, or is not developing fast enough.

A Cisco statement said that its relationship with EMC was in its 'strongest ever' state, and that EMC and Cisco were still working together in the WAFS arena: "To that end, the NAS end-of-life notice is a first step in a broader Cisco/EMC relationship that will deliver a more tightly integrated sales and marketing effort." Broader then, but possibly less deep.