SAN Transport's Truckin' in the Metro

A slew of recent announcements reflects enterprise interest in transporting SAN traffic over wide-area networks, though early assumptions about that market now look to be full of holes.

It was once thought, for instance, that enterprises would belly up to the bar for transport services specifically geared to SANs, available from specialty carriers -- the timeworn storage service provider (SSP) model. Now, it looks as if customers are more interested in getting SAN transport as part of their overall metro connectivity menu from their regular ILECs and IXCs.

Examples of these kinds of services include Ultravailability from AT&T Corp. (NYSE: T) and FibreMAN from SBC Communications Inc. (NYSE: SBC), to name just a couple.

Recent announcements indicate that SANs are being considered a key aspect of selling metro optical gear, not only to carriers providing these kinds of services, but to enterprises with the means to create their own metro networks using optical equipment:

These and other announcements contrast with struggles reported by vendors that make SAN extension equipment that's not necessarily tied to carrier transport gear. Computer Network Technology Corp. (CNT) (Nasdaq: CMNT), for instance, announced that slow IT spending cycles held back its SAN extension sales this quarter (see CNT Takes a Hit).

It's been an ongoing industry argument whether channel extenders, such as those from CNT, or SAN additions to metro optical gear for carriers were the preferred way to win over enterprise customers looking for SAN connectivity (see MSPPs Challenge Channel Extenders). At the moment, the trend seems to favor the metro approach.

"I think the service providers are well positioned to offer SAN extension services as it alleviates the need for the enterprise to buy separate standalone channel extension products," writes Jack Hunt, director of storage and photonics at Nortel Networks Ltd. (NYSE/Toronto: NT). (See EMC, Nortel Tie Optical Knot.) "By integrating the capability onto a blade in a CWDM, DWDM or Sonet/SDH MSPP the carrier can very cost-effectively offer the SAN extension service."

Another vendor says there's an organizational reason why metro equipment seems to push sales of SAN transport services. According to Todd Bundy [ed. note: no relation...], director of business development and alliances at ADVA AG Optical Networking (Frankfurt: ADAG.F), which makes carrier-grade metro optical gear, many firms send their networking groups to link data center resources across geographical areas. These groups are separate from the SAN managers in many companies, and they are so preoccupied with Ethernet, Sonet/SDH, leased lines, and other forms of data connectivity that they fail to realize that SANs can be part of the picture, too."One company was focused on optical infrastructure for LANs, and they kept talking Ethernet. I had to convince them they could benefit from interconnecting their SANs we well," Bundy says. Subsequently, the customer bought SAN modules.

Incidentally, Byte and Switch is conducting a special survey for a limited time on the subject of SAN transport services. Click here to weigh in with your views.

— Mary Jander, Site Editor, Byte and Switch