信息存储材料与技术.ppt

光电子存储材料和技术
许立新光存储光盘存储器（简称“光盘”）是利用激光原理存储和读取信息的媒介。光盘片用塑料制成，塑料中间夹入了一层薄而平整的铝膜，通过铝膜上极细微的凹坑记录信息。
只读光盘：信息是光盘制作时在盘面上一次性形成的，只能读出使用，不能重新写入。工厂通过压制方法生产光盘时，将信息以凹坑形式生成在铝膜上，成为永久的信息记录。一片普通5”只读光盘可以存放650MB的信息。只读光盘是一种非常好的可以长期保存的存储介质，今天许多商品软件和信息资料都被制成光盘销售。
刻录光盘：数据一旦进入光盘，所占的空间是不能释放的。
可读写光盘：也已投放市场。光盘和工作原理偶氮光存储基本原理电子俘获Itisestimatedthatthehumanracehascreatedabout1
exabyte(1018)ofinformationtodate.

Itisalsopredictedthatthenextexabytecouldbe
generatedwithinthenextthreeyears.

Thisunprecedentedgrowthininformationposesa
numberofsignificantchallengesintermsofinformation
storage,transmission,networking,andaccess.

Storageservicesarecurrentlygrowingat120percenta
Yearandaredirectlylinkedtothegrowthin
geographicallygeographicallydispersedonlineactivities.
Organizationsarerapidlyrealizingthattheircentraldata
storagefacilitiesarecalledonbyemployeesnotonlyin
themetropolitanarea,butworldwide.

Opticalnetworks,however,havenotbeendeveloped
andoptimizedwithdatastorageinmind,althoughitis
nowrealizedthattheyrepresentthemainsolution
availabletodayfornetworkinggeographicallydispersed
storageandusers.
Fabricattachedstorage,whichincludesstoragearea
networks(SANs)andnetworkattachedstorage(NAS),
representsoneofthefastestgrowingareasofnetworking.

Itsgoalsincludeprovidingtimelyaccesstoinformation,
largecapacity,dynamicreconfigurablebehavior,data
protectionandrestoration,aswellascoveringalarge
Geographiccoverage.

SANscanofferuniqueadvantages,including
consolidatedstoragewithcostsavingsand
reconfigurability,greaterutilityofcentralized/distributed
data,anddataprotectionthroughreplicationfordisaster
recovery.

Thisfeaturetopicprovidesanoverviewofopticalstorageareanetworks.considersnext-generationopticalstorageareanetworks
basedonthelight-trailsapproachtodynamicwavelength
provisioning.ItdiscussesSANextensionsbasedon
light-trailsandpaysattentiontoDisasterrecoveryand
gridcomputinginthecontextofSANs.

evaluatesthereliabilityandavailabilityofSANextension
solutionsincludingIPbasedextensionsandFibre
Channel(FC)-basedextens