Guideline on storage of data

8/9/2019 Guideline on storage of data

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AllOpticalDiscsareNOT

Createdequal


2/25

AllOpticaldiscsarenotcreatedequal

Why use write once optical discs forevidence storage?

Archive Grade Media

Whatqualitiesareneededforbest

performance?

Archiving Guidelines


3/25

DigitalEvidence:Whyuseopticaldiscs?

DVDDVDDVDDVD----R,CDR,CDR,CDR,CD----R,andBlueR,andBlueR,andBlueR,andBlue----raydiscsraydiscsraydiscsraydiscsareperfectlyareperfectlyareperfectlyareperfectlysuitedforlongtermstorageofevidenceorarchivaldata.suitedforlongtermstorageofevidenceorarchivaldata.suitedforlongtermstorageofevidenceorarchivaldata.suitedforlongtermstorageofevidenceorarchivaldata.

1. Computer evidence is frequently challenged in court

2. When authenticity is challenged, having data on

unalterable media is important.

3. A clause in the Federal Rules of Evidence (FRE 1001.3)

states: "If data are stored by computer or similar

device, any printout or other output readable by sight,

shown to reflect the data accurately, is an original."


4/25

TheSarbanesTheSarbanesTheSarbanesTheSarbanes----OxleyActOxleyActOxleyActOxleyAct (2002 postEnron)wasenactedin

responsetoanumberofmajorcorporateandaccountingscandals,andrequiresEmploymentofamediatechnology

thatinherentlyprotectsagainstalterationanddeletion

APartialsummaryofrequirements

fordigitaldocumentstorage:

DigitalEvidence:

Whyuseopticaldiscs?

AdurablemediumNon-rewriteableandnon-erasablestorage

Removeability/portability

Medialongevity

Backwardreadcompatibility


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DigitalEvidence:Whyuseopticaldiscs?

Recordablemediaoffers:AdurablemediumAdurablemediumAdurablemediumAdurablemediumErrorcorrectionallowsreadingthroughscratches,damage

NonNonNonNon----rewriteableandnonrewriteableandnonrewriteableandnonrewriteableandnon----erasablestorageerasablestorageerasablestorageerasablestorage

Writeonce(recordable)discscannotbealteredorerasedRemoveability/portabilityRemoveability/portabilityRemoveability/portabilityRemoveability/portability

Discsareeasilytransportedandreadinanycomputer

MedialongevityMedialongevityMedialongevityMedialongevity

MAMGoldCD-Rlife=300yrs,DVD-R100yrsBackwardreadcompatibilityBackwardreadcompatibilityBackwardreadcompatibilityBackwardreadcompatibility

CDscanbereadinDVDunits,DVDsinHD-DVDorBlu-ray

Also,AllMAM-Adiscsareserializedforuniqueidentification


6/25

ArchiveGradeMedia Howlongshoulditlast?

WhatmakesitArchiveGrade?

Whatisneededforbestperformance?

ArchivingGuidelines

DataArchivingonDataArchivingonDataArchivingonDataArchivingon

RecordableCDandDVDMediaRecordableCDandDVDMediaRecordableCDandDVDMediaRecordableCDandDVDMedia


7/25

Eventualmigrationtoanothermediaisinevitable

forlongtermdatastorage

MigrationisexpensiveItmakessensetokeepyour

dataononemediaaslongas

possible.

Startwithmediawiththe

longestexpectedlifetime.

ArchiveMedia:ArchiveMedia:ArchiveMedia:ArchiveMedia:Howlongislongenough?Howlongislongenough?Howlongislongenough?Howlongislongenough?


8/25

WhatmakesitWhatmakesitWhatmakesitWhatmakesitArchiveGradeArchiveGradeArchiveGradeArchiveGrade ????

HighPerformanceDye

Long-lifeDye

24KaratGoldReflectiveLayerUVResistant

HeatResistant

ScratchResistant


9/25

AllCD-RandDVD-Rdiscsincorporateathindyelayerthatgets

burned whenyousaveyourdata.Thestabilityofthatdyelayer

determineshowlongyourdatawillbereadable.Mitsuispatented

Phthalocyanine(thay-lo-sy-a-neen)dyeisextremelystableina

widerangeofenvironmentalconditions,providingaplatformfor

longtermdatastorage.Thedyeisthesinglemostimportant

componentforoveralldiscperformance.

Alldiscsarenotcreatedequal:Alldiscsarenotcreatedequal:Alldiscsarenotcreatedequal:Alldiscsarenotcreatedequal:

HighPerformanceDyesHighPerformanceDyesHighPerformanceDyesHighPerformanceDyes

WhenyouWhenyouWhenyouWhenyouburnburnburnburn adisc,yourwriteradisc,yourwriteradisc,yourwriteradisc,yourwriter

createscreatescreatescreatespitspitspitspits inthedyelayerthatmakeinthedyelayerthatmakeinthedyelayerthatmakeinthedyelayerthatmake

uptheuptheuptheupthe0000sandsandsandsand1111sfordigitalrecording.sfordigitalrecording.sfordigitalrecording.sfordigitalrecording.

PhthalocyaninedyereactsmorequicklyPhthalocyaninedyereactsmorequicklyPhthalocyaninedyereactsmorequicklyPhthalocyaninedyereactsmorequickly

tothewritinglaserthanotherdyes.tothewritinglaserthanotherdyes.tothewritinglaserthanotherdyes.tothewritinglaserthanotherdyes.


10/25

Phthalocyaninedyereactsina"burst"modeinsteadofa"melt"modeaswithcyanine(blue)dyes,sosharperpitedgesare

created.ThesesharperedgesareeasierforCDdrivestoread,

somorefaithfulsoundreproductionispossible;morereliable

datastorage.


MoresensitivetothewritinglaserMoresensitivetothewritinglaserMoresensitivetothewritinglaserMoresensitivetothewritinglaser


11/25


12/25

MitsuispatentedPhthalocyaninedyemakesdiscsmore

resistanttoUVlight.WhileotherdyesareveryreactivetoUVlightunlessstabilizers areadded,Phthalocyaninedyeis

naturallystable,sonoadditivesareneeded.

TheLightFastnessTestbelowshowsthatMAMCD-Rwill

withstandthefullspectrumoflight,sameasthesun,for100continuoushourswithoutdamage.Cyaninedye,beginsto

deteriorateafteronly20hoursandfailat65hours.

0

50

100

150

200

250

300

350

400

0 20 40 60 80 100

TIME(hrs)

PhthalocyaninePhthalocyanine

Cyanine

Block

Error Rate

OrangeBookStandard


UVResistanceUVResistanceUVResistanceUVResistance


13/25


Heat&HumidityResistanceHeat&HumidityResistanceHeat&HumidityResistanceHeat&HumidityResistance

0

100

200

30

0

40

0

50

0

60

0

700

800

900

1000

0

50

100

150

200250

300

350

400

Time (hours)

Heat & Humidity Test

Block ErrorRate

PhthalocyaninePhthalocyanine

Cyanine

OrangeBookStandard

Thechartbelowshowsthatacombinationofa

stablegoldreflectorandstabledyemakeforadiscwithaverylonglife.Eventhedarkercolorofsome

dyescancontributetotheamountofheatabsorbed

bythedisc.


14/25


ScratchResistanceScratchResistanceScratchResistanceScratchResistance

Thedyelayeriswhereyourdataisstored.Itliesjustbeneathseverallayersonthetopofthepolycarbonate

disc.Ifthesurfaceisdamagedbyscratchesoraballpointpen,datawillbeirretrievablylost.

Withtheuseofdigitalphotography,nonegativesexist,solossofdatacanmeanlossofyourvaluablephotos.


15/25

Formaximumsafety,thereshouldbeaprotectivelayer

thatguardsthedataagainstphysicaldamage.ThechartbelowshowsacomparisonofCD-Rmedia

subjectedtoascratchtest.Adiamondstylusispulled

acrossthetopsideofthediscwithincreasingamounts

offorceuntilthediscshowsunrecoverabledataloss.ManyCD-Rscurrentlyavailablehaveonlyathin(shiny)

lacquerlayer.


ScratchResistanceScratchResistanceScratchResistanceScratchResistance


16/25


MAM-ADVD-RLowestErrorRatesintheIndustry

WhencomparingourDVD-R

mediatocompetitors,MAMmediashowsmuchlowererrorrates.This

chartcomparesMAMPIE8error

ratestotwoleadingJapanese

brands.

Adiscisneverbetterthanthedayitleavesthefactory.Ifitstartsoutwitha

highleveloferrors,itwillonlyincreaseasthediscishandled.Eveninnormaluse discswillaccumulatescratchesordirtthatwillcausethePIE8errorstoincrease.Doesntitmakesensetostart

outwithmediathathasthefewest?

WhatisPIE8?WhatisPIE8?WhatisPIE8?WhatisPIE8?

PIE8isthenumberofdatapacketsthathaveerrorswhichcanbecorrected

bythedecoder.Themaximumallowableis280.WhenevaluatingthelifetimeofDVD,end-of-lifeisconsideredtobeatthis280limit.

(ThisisoftencomparedtoBLERforCDorCD-R)0

40

80

120

160

200

240

MaximumE

rrorrate(

PIE8Max)

MAM J1 J2


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MAM-ADVD-R-BestJitter

6.784

6.991

9.144

0

1

2

3

4

5

6

7

8

9

10

Jitter

MAM J1 J2

Jitter?Jitter?Jitter?Jitter?

Funnyname.Notmuchfunifyoucantgetyourdata

fromadiscwithhighjitter.

Thereareover130differentparameterstolookforwhenevaluatingthequalityofDVD-R

media.Lowjitterisoneofthekeycomponentsthatmanufacturersstriveforinthefactory.Ifjitterishigh,videodiscscanshowpixelationwhichcausesthepicturetobreakup.

WhatisJitter?WhatisJitter?WhatisJitter?WhatisJitter?

DataisstoredonaDVDintheformofpits,whichareareasoflowerreflectivitythatbecomethe1sand

0sthatultimatelymakeupyourvideo.Jitteristhemeasureofdifferencesinthepitlengths.Ifthesedifferencesaretoolarge,theplayerwillhaveahardtimereadingthe

information,andcouldresultinlossofdata.Thelowerthejitter,thebettertheplayback.


18/25

CalculatingLifetimeCalculatingLifetimeCalculatingLifetimeCalculatingLifetime

MAM longevity tests are conducted according to industry

standardISO18927-2002guidelines. In general, the test consists of placing samples in an

environmental chamber at specified temperature andhumiditylevelsfor5different"stressconditions".

LifeexpectancyisestimatedbasedontheuseoftheEyringmodel which is a mathematical equation derived fromthermodynamiclaws.

Based on these tests, lifetime estimates are 300 years forMAMgoldCD-Rand100yearsforMAMgoldDVD-/+R

Test Cell Test StressNumber of

Samples

Incubation

Period (hours)

Minumujm Total

Time (hours)

Min. Equilibration

Duration (hours)

1 80C, 85% RH 10 500 2000 6

2 80C, 70% RH 10 500 2000 5

3 80C, 55% RH 10 500 2000 4

4 70C, 85% RH 15 750 3000 85 60C, 85% RH 30 1000 4000 11


19/25

ArchivingGuidelinesArchivingGuidelinesArchivingGuidelinesArchivingGuidelines

FactorsAffectingtheLifetimeofDiscs GeneralStorageguidelinesfromNIST

Dos ofdischandlingandstorage

Donts

Marking


20/25

FactorsThatFactorsThatFactorsThatFactorsThat

AffectLifetimeAffectLifetimeAffectLifetimeAffectLifetime

The life expectancy of optical discs depends on many

factors, some controllable by the user, others not.

Factors that affect disc life expectancy include the

following:

type of reflective layer, type of dye

manufacturing quality

condition of the disc before recording

quality of the disc recording

handling and maintenance

storage conditions


21/25

GeneralArchivingGeneralArchivingGeneralArchivingGeneralArchivingRecommendationsfromNIST*RecommendationsfromNIST*RecommendationsfromNIST*RecommendationsfromNIST*

General recommendations for long-term storage conditions:For archiving data on recordable (R) discs, it is recommended to use

discs that have a gold metal reflective layergold metal reflective layer..

*CareandHandlingofCDsandDVDsAGuideforLibrariansandArchivists

NationalInstituteofStandardsandTechnologyTechnologyAdministration,USDeptofCommerce

Media Temperature Relative Humidity(RH)

CD, DVD 4C to 20C

(39 to 68 F)

20% to 50% RH

A temperature of 18C and 40% RH would be considered suitable for long-term storage.

A lower temperature and RH is recommended for extended-term storage.


22/25

DoDoDoDossss1. Handlediscsbytheouteredgeorthecenterhole.

2. Useanon-solvent-basedfelt-tippermanentmarkertomark

thelabelsideoftheCD-Rdisc.3. Storediscsupright(bookstyle)inplasticcasesspecified

forCDsandDVDs.

4. Returndiscstostoragecasesimmediatelyafteruse.

5. Leavediscsintheirpackaging(orcases)tominimizetheeffectsofenvironmentalchanges.

6. Openarecordablediscpackageonlywhenyouareready

torecorddataonthatdisc.

7.7.7.7. Storediscsinacool,dry,darkenvironmentinwhichtheairisclean.

8.Checkthediscsurfacebeforerecording.


23/25

Don'tsDon'tsDon'tsDon'ts

1.Touchthesurfaceofthedisc.

2.Bendthedisc.

3.Useadhesivelabels.

4.Storediscshorizontallyforalongtime(years).

5.Exposediscstoextremeheatorhighhumidity.

6.Openarecordableopticaldiscpackageifyou

arenotreadytorecord.

7.Exposediscstoextremerapidtemperatureorhumiditychanges.

8.ExposeCD-RorDVD-R/+Rdiscstoprolongedsunlightorother

sourcesofUVlight.

9.Writeormarkinthedataareaofthedisc(areawherethelaser

reads).

10.Cleaninacirculardirectionaroundthedisc.


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LabelingAreasLabelingAreasLabelingAreasLabelingAreas

AcceptableLabelingmethods:1. Waterbasedfelt-tippedpen

2. Thermalprinter

3. InkjetPrinter4. Silkscreenprinting


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Thankyou!Thankyou!Thankyou!Thankyou!

ClickonthelinkbelowtoviewtheNISTArchivingguide

CareandHandlingofCDsandDVDsAGuideforLibrariansandArchivists

OrgototheNISTsitehere

ThereisadditionalarchivinginformationatMAM-A.com

Documents

Guideline on storage of data