When our respondents were asked about their top two storage concerns, speed and performance were cited more than half of the time, at 44 percent and 10 percent respectively. Although the fastest network is only as responsive as its slowest device, it is nevertheless in your best interest to require fiber for your storage network.
But much more goes into the mix of enterprise storage networking than running lengths of fiber and hooking it up to a bunch of boxes.
Because unforeseen changes in your company, such as mergers, will upset any long-range commitments you make to a storage environment, it makes sense to plan for flexibility. Finding ways to integrate technologies and leverage the strengths of each is essential to surviving potential storage crises in the future.
Consider also the very real possibility that today's SAN technology may not live up to expectations. Although the theory behind current implementations using Fibre Channel makes sense on paper, it's floundering in execution. For example, interoperability of SAN components from multiple vendors remains elusive. Management tools are still vendor-oriented, and the relative lack of people skilled in the technology increases support costs.
It is very likely that future SANs will use IP-like protocols, although how this is to happen is an unfolding story. Traditional approaches use IP tunneling in which frames of Fibre Channel data are encapsulated in IP packets. Unfortunately, tunneling schemes slow transmission by adding latency and overhead and, essentially, only connect islands of FC-based SANs, instead of providing a truly integrated environment.
Promises for the future
One SAN vendor, Nishan Systems, of San Jose, Calif., is breaking the mold by adopting a path that integrates existing SCSI and Fibre Channel protocols with IP.
This approach, called SoIP (Storage over IP), is attractive for many reasons, the foremost being that a lot more employees understand and can support IP than Fibre Channel. Also, companies can use existing LAN, MAN (Metropolitan Area Network), and WAN hardware with Nishan's SoIP-based switches. These boxes, which debuted Feb. 5, aren't cheap -- they start at less than $10,000 -- but because a decent SAN project budget starts far beyond that, we'll ignore any instinctive sense of sticker shock.
Nishan has submitted much of the underlying protocol-level technology to the Internet Engineering Task Force (IETF), including a naming service and Fibre Channel-over-IP protocols for local and global use. (An overview is available on the IETF Web site, www.ietf.org/internet-drafts/draft-monia-ips-ifcparch-00.txt or Nishan has a summary on its site www.nishansystems.com.)