Irecently asked one of the prominent storage industry analysts what the hottest topics were for this year, and he immediately answered "storage virtualization" and "DAFS." Personally, I would have put iSCSI or IP Storage ahead of DAFS (Direct Access File System), but in fact it's unclear whether either of those will catch on this year. But there's no disagreement on whether "storage virtualization" should be included on the list of hottest topics....or is there?
There's nothing new about virtualization since main-frames have had it for decades. Early PCs exploited the concept of virtual memory in the early 1980s, and StorageTek pioneered virtual disks in its Iceberg disk array in the late 1980s. Vendors like StorageTek and IBM applied the concept to tape libraries via virtual tape (basically a RAID front-end cache on a tape library) in the 1990s. What's new is the application of virtualization in a heterogeneous storage area network (SAN) context.
If you're not up to speed on virtualization, read Dan Tanner's article, "Storage virtualization: What, how, and why," on p. 58. His short contribution provides a nice, concise definition of virtualization and a discussion of the different methodologies, design trade-offs, and benefits.
Then go back to the January issue of InfoStor and read our Special Report, "SANs rely on storage virtualization," on p. 20, which separates the various approaches to virtualization into three categories. It also takes a detailed look at implementations from nine vendors (a few more have entered the virtualization waters since then).
But beware of vendor hype. Storage virtualization is yet another catchy buzzword that vendors are bound to beat to death. It won't be long before a vendor of a SAN topology mapping tool, for instance, refers to it as "storage virtualization software."
Virtualization does, in fact, promise storage satori, but the road to illumination will require strong flashlights.
As for the Direct Access File System, stay tuned for next month's Special Report on network-attached storage (NAS), which focuses on DAFS as well as competing alternatives and other NAS boosters such as aggregation and-you guessed it-NAS virtualization.
DAFS is interesting on a number of fronts. First of all, it promises to cure the ills that have plagued NAS from the beginning. Second, it could forever blur the lines between SAN and NAS.
Also on our list of "Hot and Debatable Topics for 2001" is iSCSI or IP Storage, or in the case of Nishan Systems, SoIP (see p. 1 articles). Assuming the products live up to their promise-and at this writing, that's a big assumption-block-level storage over IP networks presents an interesting and compelling alternative to Fibre Channel in the SAN space.
Six months ago, that sort of heresy earned me a barrage of nasty letters from the Fibre Channel zealot camp. But no more, because virtually all of the Fibre Channel vendors are investing in iSCSI, either by acquisition, partnering, or R&D re-allocation.
What's your opinion about iSCSI and Fibre Channel and, for that matter, InfiniBand? Which technology will "win," and why, and how soon? Or will they all happily co-exist in a maddening protocol hodgepodge that some vendors view as a "good idea?" Drop me a line at firstname.lastname@example.org if you have an opinion.
Dave Simpson, EDITOR-IN-CHIEF
It is with great sadness that we mark the passing of Robert Poggi, publisher of InfoStor. Under Bob's leadership, Info-Stor became one of the industry's most-respected storage publications and one of PennWell Corp.'s most successful start-ups.
Bob had a long and distinguished career in trade magazine publishing and trade shows, which spanned more than 35 years and included executive positions at Benwill Publishing, Morgan-Grampian, Miller Freeman, Cahners Publishing, West World Productions, and here at PennWell. His professionalism, dedication, innate publishing skills, and no-nonsense approach to business and life made him a unique and extraordinary person.
Bob was both a colleague and friend. Our thoughts are with Bob's wife, Kathy, and family. We will miss him.