EMC & IBM in Virtual Skirmish

EMC Corp. (NYSE: EMC)and IBM Corp. (NYSE: IBM)execs agree on one thing regarding storage virtualization software: The fact that EMCs hyping its storage router is a sign of concern with IBM's presence in the market.

EMC made the storage router a focal point of presentations for its annual Analyst Day in New York Thursday -- months before that product enters beta and perhaps a year before it ships (see New EMC Group Jabs Veritas). EMC's storage router will compete with SAN Volume Controller, which IBM began shipping last year and has been making a lot of noise about lately (see IBM Revs Virtualization Engine and IBM Upgrades Virtualization ).

While IBM claims EMC is worried that Big Blue will gain too much of a competitive advantage, EMC brass say they fear IBM will give storage virtualization a bad name.

“The reason we chose to start talking about this product now is we saw products falsely introduced with the virtualization technology label,” EMC software group EVP Mark Lewis says. “We’re worried that these products will result in a negative impression in the market.”

Lewis labeled IBM’s SAN Volume Controller and the lesser-known Hewlett-Packard Co. (NYSE: HPQ) CASA (Continuous Access Storage Appliance) “limited functionality array controllers masked as virtualization routers.” Ouch!In a nutshell, EMC and IBM both plan to create appliances for storage virtualization, but they disagree about how those appliances are to work in the network.

EMC’s storage router will be an out-of-band appliance that works with intelligent switches to separate the control path in a SAN from the data path. IBM’s virtualization appliance, in contrast, is in-band, or network-based. IBM offers SVC as an appliance or a blade on a Cisco Systems Inc. (Nasdaq: CSCO) MDS 9000 switch.

What’s the difference in technologies? In-band virtualization appliances sit in the data path between hosts that store data and the targets that request it on behalf of users. Software distributes the virtual functions across the storage devices in the network and allows the host to interact with just one device. IBM says it uses caching to alleviate any latency this approach can cause.

Out-of-band appliances like EMC’s communicate with hosts and targets through SAN switches.

In-band devices are easier to deploy, sources say, but require a second box for failover and cache to alleviate the bottleneck caused by sitting in the data path. The out-of-band approach has less latency and is more scaleable, though it requires the user to buy intelligent switches.“It’s an apples-to-hubcaps comparison,” Lewis says, claiming vast superiority for the out-of-band approach.

Yes, says one IBM spokesman, but IBM is selling apples today, while EMC’s hubcaps are still in the garage.

“They recognized they need to be delivering virtualization, but they’re clearly behind the market,” says Jeff Barnett, IBM’s marketing manager for storage software. “We’re on our third version [of SVC], and by the time they come out we’ll have three more updates.”

IBM claims hundreds of customers use its storage virtualization software, including BT Group plc (NYSE: BTY; London: BTA), Blue Cross and Blue Shield of Tennessee, and Fotango, a subsidiary of Canon Europe.

So what's taking EMC so long to deliver? One reason is that EMC must port its volume management software to specific brands of intelligent switches. EMC is working with switch vendors Brocade Communications Systems Inc. (Nasdaq: BRCD), McData Corp. (Nasdaq: MCDTA), and Cisco and expects to ship product in the first half of next year (see EMC & McData Get Smart, EMC OEMs Brocade's Rhapsody Switch, and EMC, Cisco Do the Deed).Will IBM consider the out-of-band approach? Barnett says IBM won’t rule out developing software for the intelligent switch vendors, but says that will complicate the process because the switch vendors all have different architectures.

“We’ll look at the intelligent switch approach, but port-level virtualization approaches have been slow to market,” Barnett says.

HP started shipping its in-band CASA appliance last year, but momentum has slowed, and last month a jury in U.S. District Court in Massachusetts ruled that CASA infringes on three EMC patents. EMC may seek an injunction based on the verdict, while HP is contemplating an appeal (see Met Museum Mounts HP's CASA and HP Storage Takes a Hit).

— Dave Raffo, Senior Editor, Byte and Switch