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U.S. Department of the InteriorU.S. Geological Survey
Open-File Report 2010–1222
Archive and Records Management—Fiscal Year 2010 Offline Archive Media Trade Study
Archive and Records Management—Fiscal Year 2010 Offline Archive Media Trade Study
By Tom Bodoh, Ken Boettcher, Ken Gacke, Cheryl Greenhagen, and Al Engelbrecht
Open-File Report 2010–1222
U.S. Department of the InteriorU.S. Geological Survey
U.S. Department of the InteriorKEN SALAZAR, Secretary
U.S. Geological SurveyMarcia K. McNutt, Director
U.S. Geological Survey, Reston, Virginia: 2010
For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment, visit http://www.usgs.gov or call 1-888-ASK-USGS
For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprod
To order this and other USGS information products, visit http://store.usgs.gov
Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
Although this report is in the public domain, permission must be secured from the individual copyright owners to reproduce any copyrighted materials contained within this report.
Suggested citation:Bodoh, Tom, Boettcher, Ken, Gacke, Ken, Greenhagen, Cheryl, and Engelbrecht, Al, 2010, Archive and records manage-ment—Fiscal year 2010 offline archive media trade study: U.S. Geological Survey Open-File Report 2010–1222, 15 p. plus app.
iii
Preface
This document contains the Offline Archive Media Trade Study prepared by Stinger Ghaffarian Technologies, Inc. (SGT) for the U.S. Geological Survey (USGS). This trade study presents the background, technical assessment, test results, and recommendations.
v
Contents
Preface ...........................................................................................................................................................iiiAbstract ...........................................................................................................................................................1Revision History..............................................................................................................................................1
February 2004.........................................................................................................................................1September 2006 .....................................................................................................................................1June 2008................................................................................................................................................1June 2010................................................................................................................................................2
Introduction.....................................................................................................................................................2Purpose and Scope ..............................................................................................................................2Background............................................................................................................................................2Data Integrity .........................................................................................................................................2Selection Criteria ..................................................................................................................................3Dismissed Technologies ......................................................................................................................4
Magnetic Disk...............................................................................................................................4Solid State Disk (SSD) .................................................................................................................4CD-ROM, DLT 8000, QIC, Mammoth, and Erasable Optical (EO) ..........................................4Oracle 9840....................................................................................................................................4Quantum DLT.................................................................................................................................4Tandberg/Exabyte VXA320, Sony SAIT-1/SAIT-2 ....................................................................4DVD, HD-DVD, Blu-Ray ...............................................................................................................5Newer Optical Technologies ......................................................................................................5
Technical Assessment ..................................................................................................................................5Analysis ..................................................................................................................................................5Oracle T10000B......................................................................................................................................6
Advantages ...................................................................................................................................6Disadvantages ..............................................................................................................................6Summary........................................................................................................................................6
Oracle T10000C ......................................................................................................................................7Advantages ...................................................................................................................................7Disadvantages ..............................................................................................................................7Summary........................................................................................................................................7
HP LTO5...................................................................................................................................................7Advantages ...................................................................................................................................7Disadvantages ..............................................................................................................................7Summary........................................................................................................................................8
HP LTO6...................................................................................................................................................8Advantages ...................................................................................................................................8Disadvantages ..............................................................................................................................9Summary........................................................................................................................................9
IBM TS1130 ............................................................................................................................................9Advantages ...................................................................................................................................9Disadvantages ..............................................................................................................................9Summary........................................................................................................................................9
vi
IBM TS1140 ..........................................................................................................................................10Advantages .................................................................................................................................10Disadvantages ............................................................................................................................10Summary......................................................................................................................................10
Tables .............................................................................................................................................................10Design Criteria .....................................................................................................................................10Transfer Rate .......................................................................................................................................10Capacity ................................................................................................................................................11Cost Analysis .......................................................................................................................................113.5 Scenarios .......................................................................................................................................12Vendor Analyses .................................................................................................................................12Drive Compatibility ..............................................................................................................................12Ranking Summary ...............................................................................................................................13
Conclusions and Recommendations for USGS Offline Archiving Requirements ..............................13Weighted Decision Matrix .................................................................................................................13Conclusions and Notes ......................................................................................................................14Recommendations ..............................................................................................................................14
Appendix: Citations ......................................................................................................................................17Vendor Sites .........................................................................................................................................17Consortium Sites .................................................................................................................................17Other......................................................................................................................................................17
Figures 1. Screen capture showing the Oracle roadmap (uncompressed) ..........................................6 2. Screen capture showing the LTO roadmap (with 2:1 compression) ....................................8 3. Screen capture showing the IBM roadmap (uncompressed) ..............................................9
Tables 1. Recent and current archive technologies used at the U.S. Geological Survey .................2 2. Tape drive markets and characteristics ...................................................................................3 3. Technology comparison ..............................................................................................................5 4. Design criteria and target market ...........................................................................................10 5. Transfer rates ..............................................................................................................................11 6. Storage capacities .....................................................................................................................11 8. Scenario costs (drives, media) .................................................................................................12 7. Drive and media costs ...............................................................................................................12 9. Vendor analyses .........................................................................................................................12 10. Drive compatibility ......................................................................................................................13 11. Ranking summaries ....................................................................................................................13
vii
Abbreviations and AcronymsAIT AdvancedIntelligentTapeBER BitErrorRateCD CompactDiscCD-ROM CompactDisc-ReadOnlyMemoryCERN ConseilEuropeanpourlaRecherchéNucleaireCRC CyclicRedundancyCheckCPU CentralProcessingUnitDCT DigitalCassettetapeDLT DigitalLinearTapeDVD DigitalVideoDiscEO ErasableOpticalEOT EndoftapeEROS EarthResourcesObservationandScienceFYyy FiscalYearyyGB Gigabytes(1,024MB,or1,073,741,824bytes)Gbit/sec GigabitpersecondHD-DVD HighDefinitionDigitalVersatileDisc(formerlyDigitalVideoDisc)HDT HighDensityTapeHP Hewlett-PackardHVD HolographicVersatileDiscHW HardwareIBM InternationalBusinessMachinesLPDAAC LandProcessesDistributedActiveArchiveCenterLTO LinearTape-OpenMB Megabytes(1,048,576bytes)MB/sec MegabytespersecondNARA NationalArchivesandRecordsAdministrationQIC Quarter-inchCartridgeSAIT SuperAdvancedIntelligentTapeSDLT SuperDigitalLinearTapeSGT StingerGhaffarianTechnologies,Inc.SSD SolidStateDiskSTK StorageTek(subsequentlyboughtbySun,whichwasboughtbyOracle)TB Terabytes(1,024GBor1,099,511,627,776bytes)TBD ToBeDecided/DeterminedUSGS U.S.GeologicalSurvey
Archive and Records Management—Fiscal Year 2010 Offline Archive Media Trade Study
By Tom Bodoh1, Ken Boettcher1, Ken Gacke1, Cheryl Greenhagen1, and Al Engelbrecht1
1StingerGhaffarianTechnologies,Inc.,contractortotheU.S.GeologicalSurvey,workperformedunderUSGScontract08HQCN0005.
AbstractThisdocumentisatradestudycomparingofflinedigital
archivestoragetechnologies.Thedocumentcomparesandassessesseveraltechnologiesandrecommendswhichtech-nologiescouldbedeployedasthenextgenerationstandardfortheU.S.GeologicalSurvey(USGS).Archivesmustregularlymigratetothenextgenerationofdigitalarchivetechnology,andthetechnologyselectedmustmaintaindataintegrityuntilthenextmigration.Thisdocumentisthefiscalyear2010(FY10)revisionofastudycompletedinFY01andrevisedinFY03,FY04,FY06,andFY08.
Revision History
February 2004
• Addedrevisionhistorypage.NorevisionhistoryisavailablefortheFY03revision.
• Changedtoallowforconsiderationofhelicalscanaslongascertainperformancecriteriaaremet.
• AddedLinearTape-Open(LTO)2asacurrentarchivetechnology.
• AddedSuperAdvancedIntelligentTape(SAIT)-1andSuperDigitalLinearTape(SDLT)600asconsidereddrives.
• ReplacedInternationalBusinessMachines(IBM)3590withIBM3592.
• RemovedLTO1andSDLT320fromthestudy.
• Consideredalldrivesinthestudy.
• Increasedtheminimumspecificationsforcapacityandtransferrate.
• Reworkedcostscenarios,andreducedthenumberofcostscenariostothree.
• Removedtransfertimescenarios.
• Removedmaintenancefromcostscenarios.
• Removedcriteriashowingmulti-vendoravailabilityasanadvantage.
September 2006
• Overallrefreshofstudy.
• Reviseddescriptionofdriveclasses(enterprise,backup).
• AddedLTO3,TS1120,T10000,andDLT-S4ascurrenttechnologiesandremoveddrivestheyreplaced.
• AddedLTO4andSAIT-2asfuturetechnologies.
• Madevendoranalysesformulamoreequitablebyincreasingweightingofcompanyage.
• Addedcitationappendix.
June 2008
• Overallrefreshofstudy,removingmostreferencestooldertechnologies.
• Addeddiskasadismissedtechnology.
• ChangedLTO4toacurrenttechnology.
• AddedT10000B,LTO5,andTS1130asfuturetech-nologies;deletedLTO3,SAIT-1,andSAIT-2.
• Modifiedsothatfuturetechnologiesarenolongerscored.
• Decreasedthenumberofdrivesforscenarios#2and#3.
2 Archive and Records Management—Fiscal Year 2010 Offline Archive Media Trade Study
June 2010
• Overallrefreshofstudy,removingmostreferencestooldertechnologies(T10000,LTO4,DLT).
• ChangedT10000B,LTO5,andTS1130tocurrenttechnologies.
• AddedT10000C,LTO6,andTS1140asfuturetech-nologies.
• Removedmaintenancecostsduetolackofdata.
• Adjustedminimumtransferrateandcapacitytobeconsideredforthestudy.
Introduction
Purpose and Scope
Typically,thepurposeofatradestudyistoanalyzesev-eralcoursesofactionandtoprovidethenecessaryinformationforthesponsortoreachaconclusion.Inothercases,atradestudymayrevalidateanongoingcourseofaction.
Thisdocumentassessestheoptionsforthenextgenera-tionofofflinedigitalarchivestoragetechnologytobeusedforthedigitalarchivesoftheUSGS.Theselectedtechnologymustbecapableofsafelyretainingdatauntilspace,cost,andperformanceconsiderationsdrivethenextmediamigration.Datamustbemigratedbeforeintegritydegrades.
NearlyalloftheUSGSworkingarchiveholdingsnowresideonnearlinerobotictapestorageandarebackedbyanofflinemastercopy.Thenearlinecopyisreferredtoastheworkingcopy.Anongoingneedexistsforofflinestorageforinfrequentlyusedworkingcopies,andmasterandoffsitecopieswheretheworkingcopyisstorednearline.
NotethatLTO4hasbeenthearchivemediaofchoiceatUSGSforthepast2years.LTO5testingwillbegininFY10.ThereisnocompellingreasonfortheUSGStochangetechnologiesawayfromLTOatthistime,andgiventheadvantagesofintergenerationreadcompatibilityinanofflinearchiveenvironment,therewillbeacontinuedinterestin“stayingthecourse”withLTOtechnologyfortheforeseeablefuture.
ThispredispositiontouseLTOtechnologydoesnotnegatetheneedtoperiodicallyrevisitofflinestoragetechnologiestostayinformedofchanges.WhenorifLTOeventuallynolongermeetsUSGSrequirements,thisstudy(infuturerevisions)willhaveshownthewaytotheemergingreplacement.
ThisstudyspecificallydoesnotaddresstheonlineandnearlinetechnologiesusedatUSGS.Theprimarynearlinemass-storagesystemattheEarthResourcesObservationandScience(EROS)CentercontainsanHSMusinganOracleSL8500robotictapelibrary,OracleT10000/T10000Btapedrives,OracleLTO3/LTO4tape
drives,anOraclehostserver,OracleSAMHSMsoftware,andamultivendordiskcache.ThearchitectureofthisHSMwasdeterminedbyatradestudyusingadifferentsetofrequire-mentsthanthisstudy.
ThisstudydeterminesthebestofflinearchivemediatobeusedattheEROSCenterandmeetingUSGScriteria.Thefindingsofthisstudyshouldnotbemisconstruedasananalysisofanyspecifictechnologyforotherpurposessuchasenterpriseorroboticnearlinestorage.Changingthecriteriaweightingfactorswouldproducedifferentfindingstailoredtootherspecificcircumstances.
Background
TheUSGSEROSCenter,inSiouxFalls,SouthDakota,hasarchivedofflinedatasetsusingseveraltechnologies(table1).
In2003,theUSGSmigratedmorethan50,0003480and3490tapestonearlinestorageandto110LTO2tapes.Thismigrationwasperformedoveraperiodof5.5months,slowedbythehandlingofthelargenumberof3480/3490tapes.HighDensityTape(HDT),3480/3490,andDigitalCassetteTape(DCT)wereproventoberobustandhigh-performancefortheirtime.Astechnologyadvances,asdatasetsgrow,asmediaages,andasUSGSDigitalLibraryspacefills,theUSGSmustmigratedatatonewer,morephysicallycompact,andhigherperformingstoragetechnologies.
Data Integrity
Becausetheforemostgoalofanarchiveisdatapres-ervation,dataintegritymustbetheprimarycriteriafortheselectionofthedrivetechnology.Severalelementscontributetodataintegrity:
Table 1. Recent and current archive technologies used at the U.S. Geological Survey.
[Currentinbold.USGS,U.S.GeologicalSurvey;HDT,HighDensityTape;GB,gigabyte;MB/sec,megabytepersecond;MB,megabyte;DLT;DigitalLinearTape;DCT,DigitalCassetteTape;HP,Hewlett-Packard;LTO,LinearTape-Open]
Tape drive technologyYears used at
USGSCapacity Transfer rate Type
HDT 1978–2008 3.4GB 10.6MB/sec Analog3480 1990–2003 200MB 2.0MB/sec Digital3490 1995–2003 900MB 2.7MB/sec DigitalDLT7000 1996–2006 35GB 5.0MB/sec DigitalDCT(AmpexDCRsI) 1992–2007 45GB 12.0MB/sec AnalogSuperDLT220 1998–2008 110GB 10.0MB/sec DigitalOracle 9940B 2002–present 200 GB 30.0 MB/sec DigitalHP LTO Ultrium 2 2003–present 200 GB 40.0 MB/sec DigitalHP LTO Ultrium 3 2005–present 400 GB 80.0 MB/sec DigitalHP LTO Ultrium 4 2007–present 800 GB 120.0 MB/sec Digital
Introduction 3
• Thenumberofarchivalcopies:USGSarchivesmusthaveworkingandmastercopies,andanoffsitecopyisdesirable.Themasterandworkingcopiesneednotbeonsimilarmedia.
• Drivereliability:Aslightlylessreliabledrivetechnol-ogycanbeused,butonlywithasufficientnumberofcopiesinthearchive.
• Thestoragelocationandenvironment:Storagelocationandenvironmentareaconstantforallthetechnologiesassessedbecauseallmediaarestoredinasecureandclimate-controlledenvironment.
• Thecompositionofthemedia:Somemediacomposi-tionslastsignificantlylongerthanothers,butallthetechnologiesinthisstudyusesimilarlong-lastingmediacompositions.
• Tapehandlingwithinthedrive:Thischaracteristicdefineshowatapeishandledbythedrive—whethercontactismadewiththerecordingsurface,howmanyserpentinepassesarerequiredtoreadorwriteanentiretape,andthecomplexityofthetapepath.
• Errorhandling:DrivestypicallyminimizedatalossthroughCyclicRedundancyCheck(CRC)orotherdatarecoverymethods,andallowdatatobereadafterskippingpastanerror.Thougherrordetectiononwriteisrequired,additionalattentiontodatarecoveryonreadisahigherprioritybecausemediadegradationwilleventuallyleadtoreaderrors.
• Primarymarket:Thiscriteriondescribesthetargetmarketofadriveandthecharacteristicsofdrivesinthatmarket(table2).
• Adrivetargetedtothebackupmarketisdesignedforwritemany/readrarelyanddependsmoreonwriteerrordetectionbecausethedataarestillavailableandcanbeeasilyrewritten.Backupdrivesaretypicallybuiltforspeed,capacity,andlowcost.
• Adrivetargetedtotheenterprisemarketisdesignedforwritemany/readmanyuseinaroboticlibraryorauto-stacker,andequalemphasisisplacedondetectingerrorsonreadandwrite.Enterprisedrivesaretypicallybuiltforreliabilityandspeed,withcapacityasecondaryfactor.Costisanotamajorconsideration.
• Adrivetargetedtothearchivalmarketwouldbedesignedforwriteonce/readrarely,andequalemphasiswouldbeplacedondetectingerrorsonreadandwrite;however,nodrivesarecurrentlydesignedormarketedprimarilyforarchiving.Mostvendorswouldarguethattheirproductsarearchivedevices,butifforcedtochoosetheir
primarymarketnovendorwouldchoosethelim-itedarchivemarketoverthelucrativebackuporenterprisemarkets.
Thereliabilityofalong-termarchivetechnologyrelatesprimarilytothelong-termviabilityoftherecordedmedia.Reliabilityintechnologyisdifficulttodetermineexceptinretrospectbecauseatechnologyneedstobeimplementedearlyenoughinthelifecyclethatdrivescanbekeptworkingduringthelifetimeofagivenmedia(orreplacedwithnewerbackward-compatiblemodels).Thisstudybasesthereliabil-ityassessmentonpastexperiencewiththevendorandtheirproducts,onspecifications,ontheexperiencesofothers,orexperiencegainedfrombenchmarking.
Experiencewith3480,3490,9840,9940,andT10000hasshownOracle/Sun/StorageTec(STK)productstobereliable,buttheOracle/SunD3helicalscandrivewasproblematicandwasdiscontinuedquickly.OnseveraloccasionstapesthathadunrecoverableerrorsweresenttoOracleforrecovery.Sometapeswererecovered,butsomewereunrecoverablebecauseofcartridgecontamination.Tapedrivefailurestypicallyhappenwithouttapedamageandarereplacedwithoutcausingdataloss.
Selection Criteria
Thefollowingcriteriawereusedindeterminingwhichtechnologiesshouldbeconsidered.
1. Thetechnologymustbecurrentlyavailableandthemostrecentdrivemanufacturedtobeconsideredinthefinalanalysis.Drivesthatareanticipated/announcedbutnotavailablearementionedbutnotrankedinthefinalanalysis.
2. Thetechnologymusthaveatleast1terabyte(TB)[1,000gigabyte(GB)]capacityofuncom-presseddata.
3. Thetechnologymusthaveanuncompressedwritetransferrateofatleast120megabytespersecond(MB/sec).
Table 2. Tape drive markets and characteristics.
Primary market
Reliability Usage Driving design factors
Backup Moderate Writemany,readrarely
Lowcost,highcapacity,highspeed.
Enterprise High Writemany,readmany
Asmuchas100percentdutycyclefordrivesandmediausedwithrobotics.
Archive High Writeonce,readrarely
Long-termreliability.
4 Archive and Records Management—Fiscal Year 2010 Offline Archive Media Trade Study
4. Thetechnologymustusemediathatcanremainreadableforatleast10yearsinacontrolledenvironment.Thelifetimeof10yearswasselectedbecause10yearsisthelongestthatamediatechnologywouldconceivablybeusedbeforespaceandtransferrateconcernswoulddictateamovetoanewtechnology.
5. Thetechnologymustnotbehamperedbyapoorreliabilityorperformancehistory.Forexample,helicalscantechnologiessuchas4millimeter(mm),8mm,DAT,andD3haveprovenunreli-ableinthepast.
Thefollowingcurrentlyavailabledrivetechnologieswereselectedforconsideration.
1. OracleT10000B;
2. Hewlett-Packard(HP)LTO5(LinearTapeOpen)—representativeofmodelsbyIBM,Quantum,andTandberg;and
3. IBMTS1130.Thefollowingfuturedrivestechnologiesarementioned
butnotconsidered:1. OracleT10000C;
2. HPLTO6;and
3. IBMTS1140.
Dismissed Technologies
Thefollowingtechnologiesweredismissedfromanalysisorconsideration.
Magnetic DiskDiskpricescontinuetodrop,whilereliability,perfor-
mance,andcapacityincrease.Cost,managementoverhead,cooling,andpowerareconsiderationsinusingdisktoarchivelargedatasets.Inthepastseveralyearsithasbecomefeasibletostoretheworkingcopyofsomedatasets,orpartsofdatas-ets,ondiskaslongasarchivecopiesareretained,typicallyontape.Althoughtapecouldstayviableupto10years,themorecostlydiskistypicallyreplacedevery4or5yearstomaintainsupportability,reliability,andperformance.Servingfrequentlyusedworkingcopiesondiskprovidessignificantperformancebenefits,althoughanofflinemastercopymustberetained.
Solid State Disk (SSD)
Similartomagneticdisk,SSDpricescontinuetodrop,whilereliability,performance,andcapacityincrease.ItisexpectedthatSSD,overtime,willreplacemagneticdiskforonlinestorage.SSDdoesoffersomebenefitsregardingarchive
storage—itisexpectedtotoleratelongshelfstoragebetterthanmagneticdisk,whichsuffersfromcoatingdeterioration.EventhoughSSDcouldbecomeanoptionforfutureofflinearchivestorage,itistooexpensivetocompeteatthistime.
CD-ROM, DLT 8000, QIC, Mammoth, and Erasable Optical (EO)
Thiscategoryincludestechnologiesthatarelowcapac-ity,lowperformance,oraged.Alloftheseproductshavebeenavailableforsometimebutcanimmediatelybedismissedonthebasisofobviouslimitationsinperformance,capacity,orreliabil-ity.Theseproductsarenotagoodfitforlargedigitalarchives.
Oracle 9840TheOracle9840isafast-accesstechnologyusedalmost
exclusivelyinconjunctionwithOracleroboticlibraries.Althoughitisanenterprise-classdrive,ithaslowcapacity,lowtransferrate,andhighcost.Theadvantageofthisdriveisthefastaccess:thedualreeldesigndoesnotrequirealengthyloadingsequence,anditispositionedattapemidpointforfasteraccess.Althoughthistechnologyisusefulwherefastnearlineaccessisrequired,thetechnologyoffersminimalbenefitintheofflinearchivemediaarena.
Quantum DLTInpastrevisionsofthisstudy,Quantumpresentedavia-
blechallengetoLTOintheformoftheDLTline.DLThaslostsubstantialmarketsharetothepointthatfurtherdevelopmentofthelinehasbeenofficiallydiscontinued.Althoughdrivesarestillavailable,lackoffurtherdevelopmenthasensuredthatDLTisnolongercompetitivewithLTOandthespecifica-tionsdonotmeettheminimumforthisstudy.QuantumnowproducesLTOdrives.
Tandberg/Exabyte VXA320, Sony SAIT-1/SAIT-2Tandberg/Exabytehasevolvedtheirearlyhelicalscan
technologyintotheVXA320withanativecapacityof160GBandanativetransferrateof24MB/sec.Thistechnologyisbasedonconsumer-gradecartridgeanddrivetechnologies.Althoughmediacostsarelow,transferratesarealsolowandtheUSGSexperiencewithconsumer-gradestoragetechnolo-gieshasshownthatthesetechnologiescannotwithstandtherigorsofalong-termarchive.
Tapedrivessuchasthe8mm/Exabyte,whichbecamepopularinthe1990s,werebasedonconsumer-gradehelicalscantechnologyandwerenotablyslowandunreliable.Longstart/stop/repositioningtimesdictatedthatifdatawerenotkeptstreaming,theeffectivetransferratedroppeddrastically.Thenecessarilycomplexdrivepathledtoproblems:8mmdrivesmangledtapes,andaconfusingarrayoffirmwarever-sionsoftenyieldedunpredictablebehaviorandhangs.The
Technical Assessment 5
transitionfromamarketonceruledby4mm/8mmhelicalscandrivestooneruledbyLTO/DLThappenedquickly,andthesmallcurrentmarketshareofhelicalscantechnologiesmayindicatethatthemarketplacestillremembersthedif-ficultiesofearlierhelicalscandrives.Themarketmayneverreconsiderwhethertheearlierproblemsareovercomeunlessnewterminologyreplaces“helicalscan.”
TheSonySAIT-1andSAIT-2seemedpromisingwhenfirstannouncedbutwerelatetomarket,haveslowtransferrates,andnevergainedsufficientmarketsaturationtolowermediacosts.TheSAIT-2isreportedlyonlyavailableinaSonyroboticlibrary,whichistargetedtovideoautomationinthetelevisionindustry.
DVD, HD-DVD, Blu-RayDigitalVideoDisc(DVD)andrelatedtechnologiesseem
promisingfromthestandpointofexpectedlongevityofthemedia;however,studieshaveshownthatopticalmediacandegradeandbecomeunusableinaslittleas5years.Lowcapacitypermedia,lowtransferrates,lackofmediaprotec-tion(noshell),nosinglestandard,andhighmediacostsadduptoaproductthatsimplywouldnotworkforhighvolumearchivaluse.
HighDefinitionDigitalVersatileDisc(HD-DVD)waswithdrawnfromthemarketplaceafterfailingtocompetewithBlu-Ray.Blu-Raywouldcertainlyhavesomeapplicationindistributionandshort-termstorageoflargeamountsofdata,butlikeCompactDisc(CD)andDVD,Blu-Raysuffersfromhighmediacostsandlowtransferrates,andgivenopticalmediahis-tory,theshelflongevitymustbeprovenbeforebeingtrustedinanarchiveenvironment.
Newer Optical Technologies
Severalhigh-capacityopticaldisktechnologieshavebeeninthedevelopmentphaseforthepastfewyears.Ofthetechnol-ogyproposalsthathaveappearedintradejour-nalsandatconferences,noneareavailable.
Onehigh-techexampleoffuturetech-nologiesisholographicstorage.Productshavebeenrepeatedly
announced,buthaveyettoship.HolographicVersatileDisc(HVD)specificationsindicateaplannedcapacityof3.9TBperdiskandatransferrateof125MB/sec.Rivalsclaimasmuchas100TBperdiskwillbepossible.
Technical Assessment
Analysis
Thistechnicalassessmentincludesdrivesselectedforfinalevaluation(T10000B,LTO5,TS1130)anddrivesanticipatedtobereleasedinthenearfuture(T10000C,LTO6,TS1140)(table3).LTOdrivesareavailablefrommultiplevendors(Tandberg,Quantum,IBM,HP),withHPselectedtorepresentLTOtechnologyinthisstudy.Thefollowingtapetechnologieswillbeevaluated,butonlythedrivesshowninboldwillbeincludedinthefinalevaluation.
• Oracle T10000B
• OracleT10000C
• HP LTO5
• HPLTO6
• IBM TS1130
• IBMTS1140
Table 3. Technology comparison.
[Yellowhighlightedtextindicatesunverifiedinformation.HP,Hewlett-Packard;LTO,LinearTape-OpenTB,terabyte;MB/sec,megabytepersecond;TBD,tobedetermined;m/sec,meterspersecond;HW,hardware;MB,megabyte;GB,giga-byte;est,estimated]
Specification T10000B T10000C HP LTO5 HP LTO6 TS1130 TS1140Uncompressedcapacity 1.0TB 2.0TB 1.5TB 3.2TB 1.0TB 2.0TBUncompressedxferrate 120MB/sec 200+MB/sec 140MB/sec 210MB/sec 160MB/sec 240MB/secRecordingtechnology Serpentine Serpentine Serpentine Serpentine Serpentine SerpentineTracks 1,152 TBD 1,280 TBD 1152 TBDChannels 32 32 16 TBD 16 TBDPasses 36 TBD 80 TBD 72 TBDTapevelocity 3.74m/sec TBD TBD TBD 8.6m/sec TBDType Enterprise Enterprise Backup Backup Enterprise EnterpriseEncryptionsupport HWoption HWoption HWbuilt-in HWbuilt-in HWbuilt-in HWbuilt-inBuffersize 256MB 256MB 256MB TBD 1GB 1GBAdaptivespeeds 2speeds 2speeds 47–140MB/s Dynamic 6speeds MultiplePrice $24,000 $24,000est $3,200 $3,200est $29,000 $29,000estShelvescompatible? Yes Yes Yes Yes Yes YesPreviousgenerationsread 1 TBD 2 2 1 TBDPreviousgenerationswritten 0 TBD 1 1 1 TBDBitErrorRate(BER) 1x10-19 1x10-19 1x10-17 1x10-17 1x10-17 1x10-17
Drivemanufacturers 1 1 4+ 4+ 1 1Availability 2008 Late2010 2010 2012 2008 2011
6 Archive and Records Management—Fiscal Year 2010 Offline Archive Media Trade Study
Oracle T10000B
TheT10000BistheOracleflagshiphigh-capacityenter-prisedrivetypicallyusedinconjunctionwithOracleroboticlibraries,suchastheSL8500.TheEROSCenterhaseightT10000BdrivesforuseintheSL8500,inadditiontosixfirst-generationT10000drives(fig.1).
Advantages
• TheT10000Bisanevolutionofthe9940,whichtheUSGShasdeterminedtobeextremelyreliable.
• Nativecapacityis1TBandnativetransferrateis120MB/sec.TheT10000Balsocanstreamat50MB/sec,whichisimportantbecausesomedisksmaynotbeabletokeepupat120MB/sec.
• TheT10000Buses32channelsperpass(comparedto16oncompetingdrives),whichreducesserpentinepasses.With1,152tracks,only36passesarerequiredtoreadorwritetheentiretape.
• TheT10000Bistargetedtotheenterprisestoragemar-ketwheredataviability,speed,andcapacityaremoreimportantthancost.
• TheT10000Bwasdesignedasarobuststoragemedia,withthetapecartridgeanddrivebuilttowithstandconstantorfrequentuseinaroboticenvironment.ThedrivesarecompatiblewiththeSL8500andexcelinaroboticenvironmentbecauseoftheirdurability.
• T10000Bdrivesprovidedrivestatisticsforservoerrors,bytesread/written,I/Oretries,andpermanenterrors.
• T10000BusesthesamemediaastheT10000,allow-ingmediare-use.TapeswritteninT10000BformatcannotbereadbytheT10000drives.
• TheT10000Bhasa256MBbuffer,whichpreventsocca-sionaldatastarvationfromreducingthetransferrate.
• TheBitErrorRate(BER)isanindustrybestat1x10-19.
• Ahardwareencryptionoptionmoduleisavailable.
Disadvantages
• TheonlycartridgesavailableareproducedforOraclebyImationandFuji.
• TheT10000Bdrivesare7timesthepriceoftheLTO5butcheaperthantheTS1130.
• BasedonsalesoftheT10000theT10000BsalesareanticipatedtobeprimarilyforuseinOraclerobotics.Forthisreason,theT10000BisanticipatedtohaveamarketsharethatwillremainlowcomparedtoLTO,ensuringthatmediacostswillremainhigh.
• TheT10000BdriveisonlyavailablefromOracle.Thisavailabilitykeepsthepricehighbutdoeseliminateconcernsofincompatibility.
SummaryTheT10000Bisahigh-capacity,high-transferrate,enter-
prise-classdriveforuseinOracleroboticlibraries.ThecostofmediaanddrivesfarexceedsthecostofLTO,butmediareuseforfuturegenerationswouldeffectivelyreducemediacosts.Therobusttechnologywouldbeaprimechoiceforofflinearchivesifonlyonecopyofadatasetcouldbekept.Whentwoormorecopiesofadatasetexist,andoneisalreadyonanenterprisetechnologysuchasT10000B,useofanenterprisesolutionforthesecondcopyisnotwarranted.
Oracle/Sun
Figure 1. Screen capture showing the Oracle roadmap (uncompressed)
Technical Assessment 7
Oracle T10000C
TheT10000CisthethirdgenerationoftheT10000line.TheT10000Cwasoriginallyanticipatedtoshipinspring2010,butisnowexpectedtoshipinlate2010orearly2011.
Advantages
• TheT10000CisanevolutionoftheT10000/T10000B,whichtheUSGShasdeterminedtobeextremelyreliable.
• Nativecapacityisanticipatedtobeatleast2TBandnativetransferrateofatleast200+MB/sec.TheT10000Cisexpectedtostreamatlowerrates,whichisimportantbecausesomedisksmaynotbeabletokeepupat200+MB/sec.
• TheT10000Cisexpectedtouseatleast32channelsperpass(comparedto16oncompetingdrives),whichreducesserpentinepasses.
• TheT10000Cistargetedtotheenterprisestoragemar-ketwheredataviability,speed,andcapacityaremoreimportantthancost.
• ThemediafortheT10000CisexpectedtodifferfromthemediafortheT10000/T10000B,buttheT10000CmaybeabletoreadmediawrittenonT10000/T10000B.LiketheT10000media,theT10000Cmediawilllikelybedesignedasarobuststoragemedia,withthetapecartridgeanddrivebuilttowithstandconstantorfrequentuseinaroboticenvironment.ThedrivesareexpectedtobecompatiblewiththeSL8500.
• T10000Cdrivesshouldprovidedrivestatisticsforservoerrors,bytesread/written,I/Oretries,andpermanenterrors.
• Somefuturefollow-ondrivesareexpectedtousethesamemedia,allowingmediareuse.
• TheT10000Cisexpectedtohaveatleasta256MBbuffer,whichpreventsoccasionaldatastarvationfromreducingthetransferrate.
• TheBERisexpectedtobeanindustrybestat1x10-19.
• Ahardwareencryptionoptionmoduleisanticipated.
Disadvantages
• CartridgesmaybesuppliedonlybyOracle.
• TheT10000Cdrivesareexpectedtobe7timesthepriceoftheLTOandcheaperthantheTS1130.
• BasedonsalesoftheT10000,theT10000Cisantici-patedtobeprimarilyforuseinOraclerobotics.For
thisreason,themarketshareisanticipatedtoremainlowcomparedtoLTO.
• TheT10000CdriveisexpectedtobeavailableonlyfromOracle.Thisavailabilitykeepsthepricehighbutdoeseliminateconcernsofincompatibility.
SummaryTheT10000CshouldreplacetheT10000/T10000Bdrives
astheflagshiphigh-capacityenterprisedrivetypicallyusedinconjunctionwithOracleroboticlibrariesbecausetheT10000Cshouldbepricedcomparably.TheT10000Cisnotyetavail-ableand,therefore,wasnotassessedinthefinalevaluation.
HP LTO5
TheLTO5isthemostrecentavailablegenerationoftheLTOtapefamily(fig.2)andwillbetestedattheEROSCenterinlate2010.
Advantages
• LTOhasenjoyedphenomenalgrowthfromthedayofreleasein2000;asof2006,LTOheldan82percentmarketshare.Sincethen,furtherdevelopmentoftheleadingcompetingproducts(DLTandSAIT)hasbeendiscontinued.Since2006,LTOdroveDLTandSAIT-2fromthemarket.
• Nativecapacityis1.5TBandnativetransferrateis140MB/sec.
• TheHPLTO5drivecanadaptthetransferratetomatchthestreamingspeedofthesource.
• LTO5isbackwardreadcompatiblewithLTO3andLTO4,andbackwardwritecompatiblewithLTO4(atthelowerLTO4density).
• LTOwasdevelopedbyaconsortiumofHP,IBM,andQuantum(acquiredfromSeagate/Certance)andislicensedtoothers,includingmediamanufacturers.Thiswideacceptancehasintroducedcompetition,whichhasinturncontrolledcosts.
• TheLTO5hasa256MBbufferthatpreventsocca-sionaldatastarvationfromreducingthetransferrate.
• Hardwareencryptionisavailable.
Disadvantages
• LTOistargetedtothebackupmarketwherespeed,capacity,andcostaremoreimportantthanlong-term
8 Archive and Records Management—Fiscal Year 2010 Offline Archive Media Trade Study
integrityofthedata.Becausebackuptapesarewritemany/readrarely,errorswouldlikelyshowupinawritepasswheretheerrorscanbeworkedaround(rewrites)orthemediadiscarded.
• Repeatedend-to-enduseofatapewouldbeaconcernbecauseoneend-to-endread/writeincurs80passes(1,280tracksdividedby16channels).Thisrepeateduseshouldnotbeaconcernforarchiveoperationsbecauseusageislimited.
• EachgenerationofLTOrequiresnewmediatoattaintheratedcapacity,ensuringthatmediacostswillbesubstantiallyhigheruntilmarketsaturationdrivesthepricedown.Thepriceshouldnotbeaconcernforarchiveoperations,becauserequiredmedialifeistypicallysupportedbydrivebackwardcompat-ibility.
• LTOwasdesignedasamoderateusagestoragemedia,withthetapecartridgeanddrivenotbuilttowithstandconstantenterprise/roboticuse.
• LTOwasco-developedbyIBM,HP,andQuantum(acquiredfromSeagate/Certance).Thiskindofpart-nershipmakesitpossibleforeachvendortointerpretthespecificationsdifferentlyandtodesigndrivesthatmayhaveincompatibilities,thoughcompatibil-itytestsareperformed.EROSobservedtwoLTO1incompatibilityproblemsbetweenHPandIBM:tapeswrittentoend-of-tape(EOT)ontheIBMcannotbereadontheHP,andtapeswrittenontheHPreadatlessthanhalfspeedontheIBM.Inter-brandincom-patibilitiescanbeavoidedbyusingasinglebrandofdrive.
SummaryTestingofLTO5technologyatEROSwillbegininlate
2010.LTOhasbeenreliableatUSGS,withonlyasmallnum-beroffailurescommensuratewiththedesignspecificationsforamid-rangetapetechnology.
HP LTO6
TheLTO6isthenextanticipatedgenerationoftheLTOtapefamily,withreleaseanticipatedin2012basedonatypicalLTOreleasecycleof2years.
Advantages
• LTOhashadphenomenalgrowthfromthedayofreleasein2000;asof2006,LTOheldan82percentmarketshare.
• Nativecapacityisexpectedtobe3.2TBandnativetransferrateisexpectedtobe210MB/sec.
• TheHPLTO6driveisanticipatedtouseanadaptivetransferratetomatchthestreamingspeedofthesource.
• LTO6shouldbebackwardreadcompatiblewithLTO4andLTO5,andbackwardwritecompatiblewithLTO5(atthelowerLTO5capacity).
• LTOwasdevelopedbyaconsortiumofHP,IBM,andQuantum(acquiredfromSeagateCertance)andislicensedtoothers,includingmediamanufacturers.Thiswideacceptancehasintroducedcompetition,whichhasinturncontrolledcosts.
• Hardwareencryptionisanticipated.
LTO Consortium
Figure 2. Screen capture showing the LTO roadmap (with 2:1 compression)
Technical Assessment 9
Disadvantages
• LTOistargetedtothebackupmarketwherespeed,capacity,andcostaremoreimportantthanlong-termintegrityofthedata.Becausebackuptapesarewritemany/readrarely,errorswouldlikelyshowupinawritepasswheretheerrorscanbeworkedaround(rewrites)orthemediadiscarded.
• Repeatedend-to-enduseofatapewouldnormallybeaconcernbecauseoneend-to-endread/writeisexpectedtoincur80ormorepasses.Thisrepeateduseshouldnotbeaconcernforarchiveoperationsbecauseusageislight.
• EachgenerationofLTOrequiresnewmediainordertoattaintheratedcapacity,ensuringthatmediacostswillbesubstantiallyhigheruntilmarketsaturationdrivesthepricedown.Thepriceshouldnotbeaconcernforarchiveoperationsbecauserequiredmedialifeistypi-callysupportedbydrivebackwardcompatibility.
• LTOwasdesignedasamoderateusagestoragemedia,withthetapecartridgeanddrivenotbuilttowithstandconstantuse.
• LTOwasco-developedbyIBM,HP,andQuantum(acquiredfromSeagate/Certance).Thiskindofpart-nershipmakesitpossibleforeachvendortointerpretthespecificationsdifferentlyandtodesigndrivesthatmayhaveincompatibilities,thoughcompatibilitytestsareperformed.EROSobservedtwoLTO1incompat-ibilityproblemsbetweenHPandIBM:tapeswrittentoEOTontheIBMcannotbereadontheHP,andtapeswrittenontheHPreadatlessthanhalfspeedontheIBM.EROSresolvedthisissuebyonlydeployingHPdrivesforproductionuse.
SummaryLTO6isexpectedtobe
announcedin2011andmadeavail-ablein2012.LTO6isnotyetavail-ableandwasnotassessedinthefinalevaluation.
IBM TS1130
TheTS1130isanenterprise-classtapedrive,usedprimarilyinroboticlibrariesandautoloaders.TheTS1130isafollow-ondrivetotheTS1120(fig.3).
Advantages
• Lineageincludesthereliable3480,3490,3590,3592,andTS1120.
• Supportsa4gigabitpersecond(Gbit/sec)FiberChannelinterface.
• Nativecapacityis1TBandnativetransferrateis160MB/sec.
• TheTS1130isarobuststoragetechnology,withthetapecartridgeanddrivebuilttowithstandconstantorfrequentuseinaroboticenvironment.
• TheTS1130usesthesamemediaastheTS1120and3592,plusanewhighercapacitycartridge.
• Ahardwareencryptionfeatureisincludedinthedrive.
Disadvantages
• DesignedprimarilyforuseinIBMroboticlibraries.
SummaryTheTS1130doesnotcomparefavorablyincosttoLTO,
andenterprise-classrobustnessisnotrequiredwhenthework-ingcopyofadatasetisalreadyonenterprise-classtechnologyintheUSGSroboticlibrary.IBMrecentlyreporteddevelop-mentofarecordingmethodthatwillyieldacapacityof35TBpercartridge,butIBMdidnotrevealatimeline.
International Business Machines
Figure 3. Screen capture showing the IBM roadmap (uncompressed)
10 Archive and Records Management—Fiscal Year 2010 Offline Archive Media Trade Study
IBM TS1140
TheTS1140isanticipatedtobethenextgenerationofthe3592tapefamily,withreleaseexpectedin2011.NotethattheTS1140namehasnotbeenconfirmed,butfollowslogically.
Advantages
• Lineageincludesthereliable3480,3490,3590,3592,TS1120,andTS1130.
• Shouldsupporta4or8Gbit/secFiberChannelinter-face.
• Nativecapacityisexpectedtobe2TBandnativetransferratemayexceed240MB/sec.
• TheTS1140willbearobuststoragetechnology,withthetapecartridgeanddrivebuilttowithstandconstantorfrequentuseinaroboticenvironment.
• TheTS1140mayusethesamemediaastheTS1130.
• Ahardwareencryptionfeatureshouldbeincludedinthedrive.
Disadvantages
• DesignedprimarilyforuseinIBMroboticlibraries.
SummaryTheTS1140wouldnotcomparefavorablyincosttoLTO,
andenterprise-classrobustnessisnotrequiredwhenthework-ingcopyofadatasetisalreadyonenterprise-classtechnologyintheUSGSroboticlibrary.TS1140isnotyetavailableandwasnotassessedinthefinalevaluation.
Tables
Design Criteria
Thedesigncriteriaandtargetmarketofadriveareinter-related(table4).LTO5istargetedtothebackupmarket,asdemonstratedbyLTOmarketing.TheT10000BandTS1130aretargetedtotheenterprise(datacenter)market.
Adrivetargetedtothebackupmarketisdesignedforwritemany/readrarelyanddependsonwriteerrordetectionbecausethedataarestillavailableandcanbeeasilyrewritten.Backupdrivesaretypicallybuiltforspeed,capacity,andlowcost.
Adrivetargetedtotheenterprisemarketisdesignedforwritemany/readmanyuseinaroboticlibraryorauto-stacker,andequalemphasisisplacedondetectingerrorsonreadandwrite.Enterprisedrivesaretypicallybuiltforreliabilityandspeed,withcapacityasecondaryfactor.Costisnotamajorconsiderationtoenterpriseuserswillingtopayforquality.
Adrivetargetedtothearchivalmarketwouldbedesignedforwriteonce/readrarely,andmoreemphasiswouldbeplacedondetectingandcorrectingerrorsonread;however,therearecurrentlynodrivesdesignedormarketedprimarilyforarchiveuse.
Theformulausedtorankdesigncriteriawas:
((100-serpentinepasses)/10)+(absolutevalueoferrorrateexponent/2)+
(construction3=moderateusage,5=highusage)+(headcontact3=contact,5=mincontact)/2.59(toadjustthehighestrankto10)
Transfer Rate
Transferrateisimportantbecauseitestablisheshowquicklythemigrationofanarchivedatasetmaybecompleted
Table 4. Design criteria and target market.
[Uncorrectederrorratesforsomedrivesarenotavailablebutarepresumedtobeeitherthesameastheirpredecessororatleast1x10-17.Yellowhighlightedtextindicatesunverifiedinformation.MP,metalparticle;TBD,tobedetermined;HP,Hewlett-Packard;LTO,LinearTape-Open;IBM,InternationalBusinessMachines]
TechnologySerpentine
tracks/ passes
Target market
Tape composition
Uncorrected error rate
Cartridge construction
ratingHead contact Ranking
OracleT10000B 1,152/36 Enterprise AdvancedMP 1x10-19 Highusage Minimumcontact 10.0OracleT10000C TBD Enterprise AdvancedMP 1x10-19 Highusage Minimumcontact 10.0HPLTO5 1,280/80 Backup ThinfilmMP 1x10-17 Moderateusage Contact 6.4HPLTO6 TBD Backup ThinfilmMP 1x10-17 Moderateusage Contact 6.4IBMTS1130 1,152/72 Enterprise AdvancedMP 1x10-17 Highusage Contact 8.2IBMTS1140 TBD Enterprise AdvancedMP 1x10-17 Highusage Contact 8.2
Tables 11
andhowfastaproductionsystemmaygenerateproductsfromthearchivemedia.Theminimumtransferraterequirementis120MB/sec,with140MB/secdesired.MuchofthedataarchivedattheUSGSarerasterimagerythattypicallylackrepeatablepatternsthatwouldcompresswell;therefore,alltransferratescitedarenative(uncompressed).
Wheremeasuredtransferrateswerenotavailable,approximateratesaredeterminedbasedontheaccuracyofspecifiedtransferratesofpreviousgenerations.Thesourceofthetestresultsalsoappliestocapacitiesintable5.
Therankingwasdeterminedbyaddingtheactual/approx-imatereadandwriteratesforeachdrive,settingtherankingforthefastestdriveto10,thenrankingtheothersagainsttheleader.Forexample,adrivehavinghalfofthetotalread/writetransferrateoftheleaderwouldberanked5.
Capacity
Asecondaryrequirementistoconserverackorpal-letstoragespaceandreducetapehandlingbyincreasingpermediacapacity.ThecurrentarchivemediaofchoiceattheUSGSisLTO4at757GBofusablecapacitypertape.Thenewminimumcapacityrequirementis1TB,with1.5TBor
moredesired.Allthereviewedtechnologiesmeetthe1TBrequirementbasedontheadvertisedcapacity.Becausemuchofthedataarchivedarenotcompressible,allcapacitiesarenative(uncompressed).Wheremeasuredcapacitieswerenotavailable,approximatecapacitiesaredeterminedbasedontheaccuracyofspecifiedcapacitiesofpreviousgenerations.
Thecapacitieslistedintable6presumethatagigabyte=1,073,741,824bytes.Theratingsweredeterminedbycomput-ingeachasthepercentageofthehighestcapacitydriveonascaleof1to10,withthehighestcapacityasa10.Thesourceofthecapacityratingsarenotedintable6.Notethatcapacityyieldvariesbymediavendor.
Cost Analysis
Table7showstherelativedriveandmediacosts,drivewarranty,andthecostperterabyteformedia.Rankingswereestablishedbysettingthecheapest(driveandmedia)to10thenratingeachoftheothersagainstthelowestcost.Mediacostsperterabytearebasedonadvertisedcapacity.Costsdonotincludesysteminterfacesorcables.PricesarebasedonthelowestpricefoundontheWeborongovernmentpricelists.
Table 5. Transfer rates.
[Yellowhighlightedtextindicatesunverifiedinformation.EROS,EarthResourcesObservationandScience;HP,Hewlett-Packard;LTO,LinearTape-Open;IBM,InternationalBusinessMachines;MB/sec,megabytepersecond]
Tape drive technology
Advertised/ proposed native
rate
Source of test results
Actual/approximate native write transfer rate
Advertised capacity
(in percent)
Actual/approximate native read transfer rate
Advertised capacity
(in percent)Ranking
OracleT10000B 120MB/sec EROStesting 109.00MB/sec 91 120.00MB/sec 100 7.4OracleT10000C 180MB/sec Approximate 163.80MB/sec 91 180.00MB/sec 100 7.4HPLTO5 140MB/sec Approximate 126.70MB/sec 90.5 126.56MB/sec 90.4 8.2HPLTO6 210MB/sec Approximate 190.05MB/sec 90.5 189.84MB/sec 90.4 8.2IBMTS1130 160MB/sec Vendor 153.92MB/sec 96.2 153.92MB/sec 96.2 10.0IBMTS1140 240MB/sec Approximate 230.88MB/sec 96.2 230.88MB/sec 96.2 10.0
Table 6. Storage capacities.
[Yellowhighlightedtextindicatesunverifiedinformation.TB,terabyte;GB,gigabyte,HP,Hewlett-Packard;LTO,LinearTape-Open;IBM,InternationalBusinessMachines]
Tape drive technologyAdvertised/
proposed native capacity
Measured/approximate native capacity
Advertised capacity
(in percent)Ranking
OracleT10000B 1.0TB 936GB 93.6 6.6OracleT10000C 2.0TB 1,872GB 93.6 6.6HPLTO5 1.5TB 1,420GBapproximate 94.7approximate 10.0HPLTO6 3.2TB 3,030GBapproximate 94.7approximate 10.0IBMTS1130 1.0TB 950GBapproximate 95.0approximate 6.7IBMTS1140 2.0TB 1,900GBapproximate 95.0approximate 6.7
12 Archive and Records Management—Fiscal Year 2010 Offline Archive Media Trade Study
MaintenanceshouldbeaconsiderationbutwasremovedfromthisiterationofthestudybecauseofthetenuousstatusofOraclesupportcostsasofthiswriting,andincompleteinfor-mationonLTOsupport.Maintenancewillbereconsideredinthenextupdate.
3.5 Scenarios
Table8showsthetotaldriveandmediacostforthreescenarios.Thesescenariospresumethateachdatasetorprojectstandsalone,althoughpoolingresourcesformultipledatasetscanmitigatecost.Competitionoftenresultsinaconsider-abledropinmediapriceswithin6monthsafterproductintroduction.
Rankingsarebasedonthe100TBoptionandwereestablishedbysettingthecheapestto10thenratingeachoftheothersagainstthelowestcost.Advertised/proposednativecapacitiesareused.Costsdonotincludemaintenance,systeminterfaces,orcables.
Thoughnotrepresentedinthisstudy,technologyrefreshcostsrelatedtomovingfromonegenerationtothenextmayvarydependingonwhetherthevendorrequiresamediachange.LTOhasalwaysrequirednewmediaforeachgenera-tion,butOracleandIBMtypicallyhaveusedthesamemediaforatleasttwogenerations.
Vendor Analyses
Table9providesananalysisofeachcompanyandthestabilityofeachtechnology.Allareestablishedandstablecompanies;therefore,thisratingshouldnotbeviewedasamarketanalysis.Whenselectinganarchivetechnology,itmakessensetolookatthecompanyandproducthistorieseventhoughratingvendorhistoryischallengingbecauseofmergersandacquisitions.ForT10000B,thetechnologywasbasedonthepredecessor9940;therefore,thetechnologyageincludesthe9940.Thelongevityrankingsweredeterminedbythefol-lowingformula:
(companyage+technologyage)/11.4(toadjustthehighestrankto10)
Determiningcompanyyearsinbusinessiscomplicatedbymergersandacquisitions,suchaswhenSunacquiredSTKandwaslateracquiredbyOracle.TheyearsinbusinessbeganwithSTKbecausethetapetechnologyofferedtodayisbasedonSTKproducts.Thepurposeofthissectionistoassesstech-nologylineageandcompanyhistory,butmergersandacquisi-tionsmaybedistractiveanddetrimentalwhenconsideringlineageandhistory.
Drive Compatibility
Table10showsthelevelofintergenerationdrivecompat-ibilityandthefuturedrivesplanned.Thecolumns“Percentageofpreviousgenerationsread”and“Percentageofprevious
Table 7. Drive and media costs.
[Yellowhighlightedtextindicatesunverifiedinformation.TB,terabyte;est,estimated:HP,Hewlett-Packard;LTO,LinearTape-Open;IBM,InternationalBusinessMachines]
TechnologyDrive
(dollars per each)Drive
warranty
Media (dollars
per each)
Media (dollars per TB)
Ranking drive cost
Ranking media cost
per TBOracleT10000B $24,000 12month $125 $125 1.3 5.6OracleT10000C $24,000est 12month $125est $62est 1.3 5.6HPLTO5 $3,200 36month $105 $70 10.0 10.0HPLTO6 $3,200est 36month $105est $33est 10.0 10.0IBMTS1130 $29,000 12month $178 $178 1.1 3.9IBMTS1140 $29,000est 12month $178est $89est 1.1 3.9
Table 8. Scenario costs (drives, media).
[Yellowhighlightedtextindicatesunverifiedinformation.TB,terabyte;HP,Hewlett-Packard;LTO,LinearTape-Open;IBM,InternationalBusi-nessMachines]
Technology100 TB
2 drives200 TB
3 drives400 TB
4 drives100 TB
ranking
OracleT10000B $60,500 $97,000 $146,000 2.2OracleT10000C $54,250 $84,500 $121,000 2.2HPLTO5 $13,435 $23,565 $40,730 10.0HPLTO6 $9,700 $16,200 $26,000 10.0IBMTS1130 $75,800 $122,600 $187,200 1.8IBMTS1140 $66,900 $104,800 $151,600 1.8
Table 9. Vendor analyses.
[STK,StorageTek;HP,Hewlett-Packard;LTO,LinearTape-Open;IBM,InternationalBusinessMachines]
Company TechnologyYears in business
Technology age, in years
Longevity ranking
Oracle/Sun/STK T10000 41(1969) 10(2000) 4.5HP LTO 71(1939) 10(2000) 7.1IBM 3592(3590) 99(1911) 15(1995) 10.0
Conclusions and Recommendations for USGS Offline Archiving Requirements 13
generationswritten”indicatethepercentageofpreviousgenerationsthatareread/writtenbythegenerationindicated.Drivesthatarethefirstgenerationreceiveascoreof50per-cent,sothefirstgenerationproductwillnotbepenalized.Thecolumn“Futuregenerationsplanned”indicatesthenumberofgenerationsplannedinthecurrentdrivefamily,followingthedriveindicated.Therankingwasdeterminedbythefollowingformula:
(Percentageofpreviousgenerationsread+Percentageofpreviousgenerationswritten+
(Futuregenerationsplannedx20))/21(toadjust
thehighestrankto10)
Ranking Summary
Therankingsummaryprovidesaquickreferencetotherankings(table11).
Conclusions and Recommendations for USGS Offline Archiving Requirements
Weighted Decision Matrix
Table12providesaweightedanalysisofthedrivesconsidered.Thecriteriaemphasizetheimportanceoftraitscontributingtodatapreservation.TheUSGSmadethefinaldecisionregardingwhichcriteriatouseandtherelativeweightingofthecriteria.Thecolumnsingreenarerelativeratingsforeachtechnology.Thecolumnsinyellowarecalcu-latedbymultiplyingtherelativeweightbytherelativerating.Thefollowinglistdescribeseachcriterion:
• Design(reliabilityofmedia):Thiscriteriondescribestheabilityofthemediatoremainreadableovertime.Includedinthiscriterionisthenumberofpassesperfull-tapereadorwrite,cartridgeconstruction,uncor-rectedBER,andamountofheadcontact(table4).
• Capacity:Thiscriteriondescribesthemeasuredorapproximatecapacitypercartridge,whichistypicallylessthantheadvertisedcapacity(table6).
• Mediacost/TB:Thiscriterionisaratingoftherelativecostperterabyteformediausingtheadvertisedcapac-ity(table7).
• Compatibility:Thiscriteriondescribesthelikelihoodthatthedrivetechnologywillcontinuetoevolveandtheextenttowhichfuturedriveswillhavebackwardreadandwritecapability.Thiscriterionwillgiveanindicationoftheabilitytomaintaindrivesthatcanreadanagingarchive(table10).
• Transferrate:Thiscriteriondescribestheaggregatereadandwritetransferrate,whichistypicallylessthantheadvertisedtransferrate(table5).
Table 10. Drive compatibility.
[Yellowhighlightedtextindicatesunverifiedinformation.HP,Hewlett-Pack-ard;LTO,LinearTape-Open;IBM,InternationalBusinessMachines]
Technology
Percentage of previous generations
read
Percentage of previous generations
written
Future generations
plannedRanking
OracleT10000B 100 0 3 7.6OracleT10000C 100 0 2 7.6HPLTO5 50 25 3 6.4HPLTO6 40 20 2 6.4IBMTS1130 100 50 3 10.0IBMTS1140 100 50 2 10.0
Table 11. Ranking summaries.
[Blueindicatesthehighestrankingincategory.HP,Hewlett-Packard;LTO,LinearTape-Open;IBM,Interna-tionalBusinessMachines]
DriveDesign criteria
CapacityMedia
costDrive
compatibilityTransfer
rateDrive cost
Vendor analyses
Scenario cost
T10000B 10.0 6.6 5.6 7.6 7.4 1.3 4.5 2.2HPLTO5 6.4 10.0 10.0 6.4 8.2 10.0 7.1 10.0IBMTS1130 8.2 6.7 3.9 10.0 10.0 1.1 10.0 1.8
14 Archive and Records Management—Fiscal Year 2010 Offline Archive Media Trade Study
• Drivecost:Thiscriterionistheratingofrelativecostofeachdriveatthelowestcurrentlyavailableprice(table7).
• Vendoranalyses:Thiscriterionistheratingoftheviabilityofthevendorandtechnology(table9).
• Scenariocost:Thiscriterionistheratingofthecostofscenario#1,whichcomprisesmediacostanddrivecost.Themeasuredorapproximatecapacityisusedratherthanadvertisedcapacity(table8).
Notethatinthedecisionmatrixspreadsheetlistedintable12,notallcriteriahavebeenselectedforthefinalanalysisofthistradestudy.Theseunusedcriteriawereleftinthespread-sheetsothatusersmayinsertthecriteriaweightsfortheirspecificapplication.
Conclusions and Notes
LTO5achievedthehighesttotalscoreinthestudy;there-fore,nocompellingreasonexiststoabandonLTOtoadoptanewstandardofflinearchivetechnology.
LTO5andTS1130werenotavailabletobetestedforthisstudy;therefore,performanceandcapacityfigureswerebasedonvendororcustomerbenchmarkswhereavailableorondrivespecificationscombinedwithpastperformance(percent-ageoftheclaimedspecificationsthatwereachievableinthepast).
• Whenmultiplecopiesofadatasetaremaintained,trad-ingcostandperformanceforreliabilityisacceptable,particularlywhentheworkingcopyisonanenterprisetechnologysuchasOracleT10000B,asaremostarchivesatUSGS.
• Asanydrivesaturatesthemarket,mediaanddrivecostsdrop.BasedonUSGSexperiencewithenterprisetapetechnologyandobservationofOracleandIBM
pricing,enterprisedrivessuchastheT10000BandTS1130areunlikelytoachievealevelofmarketsatu-rationthatwouldcausesubstantialpricedecreases.
• Withproperhandlingandmultiplecopies,anyofthetechnologiesevaluatedinthisreportcouldbedeployedforarchiveuse.Whenmorethantwocopiesexist,allcouldbeonnon-enterprisetechnology.
Recommendations
1. TheUSGSshouldcontinuewithLTO4astheofflinestoragemediaofchoice,thentestandmovetoLTO5,whenavailable.
2. DatastoredonLTO2andLTO3shouldbemigratedtoLTO5inthenext2years.
3. Toreducerisk,theUSGSshouldcontinuethestrategyofstoringdatasetsonmultipletechnologieswhenonlytwocopiesexist.Forexample,storeaworkingcopyofadatasetonnearlineT10000Bandoffline/offsitecopiesonLTO.Thisstrategypartlymitigatestherisksofoneortheothertechnologyfailingorbeingretiredprematurely.
4. Inadditiontoanearlineandoffsitecopyofadataset,anonsiteofflinecopyshouldbemaintained,provid-ingfastrecoverywithoutriskingtheshippingoftheoffsiteLTOcopy.
5. TheUSGSshouldadoptapolicyofperiodicallytest-ingarchivetapesforreadability.ThistestingshouldnotbeextensiveenoughtoincurunduewearonthemediaorfrustratetheNationalArchivesandRecordsAdministration(NARA),butshouldbefrequentenoughtoprovideanopportunitytodetectdeterio-ratingmedia.
Table 12. Weighted decision matrix.
[TB,perterabyte]
Selection criteria WeightOracle
T10000BHP
LTO5IBM
TS1130Oracle
T10000BHP
LTO5IBM
TS1130
Designcriteria 0 10.0 6.4 8.2 0.0 0.0 0.0Capacity 20 6.6 10.0 6.7 132.0 200.0 134.0MediacostperTB 0 5.6 10.0 3.9 0.0 0.0 0.0Compatibility 15 7.6 6.4 10.0 114.0 96.0 150.0Transferrate 15 7.4 8.2 10.0 111.0 123.0 150.0Drivecost 0 1.3 10.0 1.1 0.0 0.0 0.0Vendoranalyses 15 4.5 7.1 10.0 67.5 106.5 150.0Scenariocost 35 2.2 10.0 1.8 77.0 350.0 63.0 Totalweightedscore 501.5 875.5 647.0
Conclusions and Recommendations for USGS Offline Archiving Requirements 15
6. Allarchivedfilesshouldbechecksummedandthechecksumstoredinthecorrespondinginven-toryrecord.WhenafileisretrievedfromeithertheSiloortheofflinemedia,integritycanbeverified.VerificationofeachretrievedfilemaynotbefeasiblebecauseofCPUimpacts.
7. Alldatashouldbemigratedtonewmediafrom3to5yearsafteritwaswritten.Althoughmosttapetechnologiescanreliablystoredataformuchlongerperiods,after5yearsthetransferratesanddensitiesthatoncewereleadingedgewillbecomeproblematic,anddriveswillbecomedifficulttomaintain.ThisisabestpracticesupportedbyNARA.
8. Whenwritingarchivetapes,thetapesshouldbeverifiedonaseconddrive.Thisverificationwillhelp
identifyanydriveincompatibility.Thispracticehasbeenimplementedandshouldcontinue.
9. Eachtimethisstudyisrevisited,thehighestscor-ingtechnologymaychange.ThischangedoesnotindicatethattheUSGSshouldchangeofflinetapetechnologiesfrequently.Stayingwithagiventech-nologyforseveralyearsisabenefit,evenifthetech-nologyisnottheleadingtechnologycontinuously.Thisstudyisasnapshotintime,andresultswoulddifferevenafewmonthsearlier/laterbecauseofnewhardwarereleases.TherecurrentlyisnocompellingreasontoabandonLTOtechnology.
10. TheUSGSshouldplantoupdatethistradestudyperiodically.Annuallymaybetoofrequenttoobservemarketchangesbecausedrivesaretypicallyupdatedona2-or3-yearcycle.
Appendix: Citations 17
Appendix: Citations
Vendor Sites
http://h18006.www1.hp.com/storage/tapestorage/tapedrives.html (Hewlett-Packard)
http://www.oracle.com/us/products/servers-storage/storage/tape-storage/index.htm (Oracle)
http://www-03.ibm.com/servers/storage/tape/index.html (International Business Machines)
http://www.quantum.com/Products/TapeDrives/Index.aspx (Quantum)
http://www.tandbergdata.com/us/en/products/drives/lto/ (Tandberg)
Consortium Sites
http://www.lto.org/newsite/index.html
Other
http://www.clipper.com/research/TCG2004040.pdf
http://www.redbooks.ibm.com/redbooks/pdfs/sg244632.pdf
http://www.computerworld.com/hardwaretopics/storage/story/0,10801,110667,00.html?source=NLT_SU&nid=110667
http://www.informationweek.com/news/showArticle.jhtml?articleID=187203674
http://www.techworld.com/storage/news/index.cfm?newsID=5888&pagtype=samechan
http://en.wikipedia.org/wiki/Holographic_Versatile_Disc
http://www.norsam.com/hdrosetta.htm
http://www.theregister.co.uk/2007/03/21/lto_beats_dlt/
https://www.bluestoragemedia.com/External/BigBlueBytes/Product%20Information/3592%20Gen%202/IBM%20System%20Storage%20TS1120%20Tape%20Drive%20Training%20Presentation.pdf
http://www.techworld.com/storage/features/index.cfm?featureid=3728
http://www.imation.com/euc/pdfs/EUC_07_Kenyon.pdf
http://www-03.ibm.com/systems/storage/tape/ts1130/index.html
http://h10010.www1.hp.com/wwpc/us/en/sm/WF25a/12169-304612-3446236-3446236-3446236-4150338.html
http://dlc.sun.com/pdf/316194802B/316194802B.pdf
18 Archive and Records Management—Fiscal Year 2010 Offline Archive Media Trade Study
http://www.lto-technology.com/pdf/2006-7-25.pdf
http://itknowledgeexchange.techtarget.com/storage-soup/hp-quantum-in-cahoots-for-lto-5/
http://www.itjungle.com/fhs/fhs020508-story10.html
http://searchdatabackup.techtarget.com/news/article/0,289142,sid187_gci1355225,00.html
http://www-03.ibm.com/press/us/en/pressrelease/29245.wss
http://en.wikipedia.org/wiki/Linear_Tape-Open
http://www.infoworld.com/d/data-explosion/tape-dead-long-live-tape-090
http://www.engadget.com/2010/02/08/inphase-out-of-business-assets-seized-for-back-taxes/
http://h20195.www2.hp.com/v2/GetPDF.aspx/4AA0-7675ENW.pdf
ftp://service.boulder.ibm.com/storage/tape/clipper.pdf
Appendix: Citations 19
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