Quantum Releases SuperDLT
Thedominant midrange backup tape format has a new iteration. Quantum is shippingits SuperDLT drives, the successor to the popular DLT line of tapes and drives.
DLT hasbeen the dominant midrange backup in the market, becoming the de facto standardfor archiving and restoring midrange servers in the enterprise. SuperDLT buildson the successful format by fattening capacity and speeding up write time.
Like itspredecessor, SuperDLT uses a single-reel, half-inch magnetic tape with a linearrecording pattern. SuperDLT’s optical tracking mechanism, however, sets itapart from the DLT line. An optical track is recorded on the back side of thetape and is read by a laser while keeping the tape on the head. As a result,the normal up and down movement of the tape is reduced, allowing more of thetape width to be used.
The opticaltracking system improves the accuracy of the systems, and permits a greaternumber of narrower bands to be placed on the same width of tape, exponentiallyincreasing capacity.
Quantumalso has incorporated some technologies from the hard-drive world into its tapetechnologies. According to Bob Abraham, president of Freeman Reports Inc.,SuperDLT is the first compact tape family to feature a cluster head.
Inaddition, SuperDLT employs Partial Response Maximum Likelihood (PRML) encodingto increase the amount of data stored in a physical space. PRML is standard indisk drives, but Abraham says there were issues in the past concerning PRML usein sequential recording.
SuperDLTtapes top out at 110-GB storage and 11 MBps transfer rates. Quantum is alsoreleasing a version for the file-and-print level that holds 80 GB with 8 MBpstransfer rates. Quantum says its roadmap plans for eight product generationsbased on the SuperDLT platform, increasing capacity and transfer rates witheach iteration.
The newSuperDLT drives will eventually be backward-compatible with the existing DLTproduct line. In addition, SuperDLT drives will support the DLT1 line of tapesintroduced by Benchmark Technologies.
Majorlibrary vendors, including Advanced Digital Information Corp. (ADIC), StorageTek,and Overland Data, signed on to build libraries using SuperDLT.
The firstSuperDLT products will not be backward-compatible with the DLT line, but thisis not expected to be a disadvantage because primary competitor LTO has noprevious generations to support. Abraham says he expects library manufacturers,Quantum’s primarily early customers, to build enhanced DLT8000 librariescontaining both DLT8000 and SuperDLT tapes and drives. He says addingfunctionality later is a reasonable strategy for Quantum: “It gives them alittle bit of lead time.”
DLT mayhave gained its dominance due to a relative scarcity of tape platforms for themidmarket space, but SuperDLT faces some stiff competition. The LTO program wasspecifically designed to usurp DLT’s throne, plus it has a head start onSuperDLT. A consortium of IBM, Seagate, and Hewlett-Packard designed LTO.
Abrahamsays the few weeks lead time should not give LTO vendors an advantage overQuantum. Resellers and library manufacturers had a good sense of when theSuperDLT line would hit the market, so few companies made plans based on theearlier product release that would affect Quantum’s sales.
Exabyte hasbeen shipping its Mammoth-2 line of tapes since late last year. “Until [therecent LTO and SuperDLT announcements] Exabyte had the leading-edge tapeproduct,” Abraham says. “They were very successful in terms of gainingmindshare.” He says Exabyte is expect to leapfrog Quantum and the LTOconsortium again when it ships the Mammoth-3 line of tape next year.
Quantum Corp., Milpitas,Calif., www.quantum.com