© 2009 EMC Corporation. All rights reserved. EMC Proven Professional The #1 Certification Program in the information storage and management industry Content Addressed Storage Chapter 9 Section 2 : Storage Networking Technologies and Virtualization

© 2009 EMC Corporation. All rights reserved. Chapter Objectives Upon completion of this chapter, you will be able to: oDescribe CAS, fixed content and archives, traditional storage solutions for archive oDescribe the features and benefits of a CAS based storage strategy oList the physical and logical elements of CAS oDescribe the storage and retrieval process for CAS data objects oDescribe the best suited operational environments for CAS solutions

© 2009 EMC Corporation. All rights reserved. Lesson: CAS Overview Upon completion of this lesson, you be able to: oDefine fixed content oDescribe traditional archival solutions and its shortcoming oDefine Content Addressed Storage (CAS) oList benefits of CAS

© 2009 EMC Corporation. All rights reserved. What are Fixed Content and Archives Not a specialized form of data Stored using optical disks to tapes to magnetic disks. Users: Demand assurance that stored data has not changed and require immediate online access to fixed content. Data is actively created, accessed, edited and changed. As data ages, it becomes less likely to change and eventually becomes ‘fixed’ but continues to be accessed by multiple applications and users. This data is called ‘fixed content’. Data is actively created, accessed, edited and changed. As data ages, it becomes less likely to change and eventually becomes ‘fixed’ but continues to be accessed by multiple applications and users. This data is called ‘fixed content’.

© 2009 EMC Corporation. All rights reserved. What are Fixed Content and Archives Electronic Documents Contracts, claims, etc. and attachments Financial spread sheets CAD/CAM designs Presentations Digital Records Documents – Checks, securities trades – Historical preservation Photographs – Personal / professional Surveys – Seismic, astronomic, geographic Digital Assets Retained For Active Reference And Value Leverage Historical Value Improve Service Levels Generate New Revenues Rich Media Medical – X-rays, MRIs, CTI Video – News / media, movies – Security surveillance Audio – Voic – Radio

© 2009 EMC Corporation. All rights reserved. Challenges of Storing Fixed Content oFixed content is growing at more than 90% annually oSignificant amount of newly created information falls into this category oNew regulations require retention and data protection oOften, long-term preservation is required (years-decades) oSimultaneous multi-user online access is preferable to offline storage oNeed faster access to fixed content oNeed for location independent data, enabling technology refresh and migration oTraditional storage methods are inadequate

© 2009 EMC Corporation. All rights reserved. Traditional storage solutions for Archive oThree categories of archival solution are: oOnline: the storage device is directly connected to the host to make the data immediately available. oNearline: the storage device is connected to the host and information is local, but the device must be mounted or loaded to access the information. oOffline: The storage device is not directly connected, mounted or loaded. Manual intervention is required to provide this service before information can be accessed. Traditional archival solution were offline oTraditional archival process used optical disks and tapes as media for archival oAn archive is often stored on a Write Once Read Many (WORM) device, such as a CD-ROM

© 2009 EMC Corporation. All rights reserved. Shortcomings of Traditional Archiving Solutions oTape is slow, and standards are always changing oOptical is expensive, and requires vast amounts of media oRecovering files from tape and optical is often time consuming oData on tape and optical is subject to media degradation oBoth solution require sophisticated media management CAS has emerged as an alternative to traditional archiving solutions

© 2009 EMC Corporation. All rights reserved. What is Content Addressed Storage (CAS) oObject-oriented, location-independent approach to data storage oRepository for the “Objects” oAccess mechanism to interface with repository oGlobally unique identifiers provide access to objects

© 2009 EMC Corporation. All rights reserved. Benefits of CAS oContent authenticity oContent integrity oLocation independence oSingle-instance storage (SiS) oRetention enforcement oRecord-level protection and disposition oTechnology independence oFast record retrieval Additional Task Research on role of CAS in ILM Strategy

© 2009 EMC Corporation. All rights reserved. Lesson Summary Key points covered in this lesson: oCAS Definition oChallenges of Storing Fixed Content oShortcomings of Traditional Archiving Solutions oBenefits of CAS

© 2009 EMC Corporation. All rights reserved. Lesson: CAS Architecture Upon completion of this lesson, you will be able to: oDescribe CAS architecture oDescribe Physical and logical elements of CAS oDescribe data storage and retrieval process in CAS environment oCAS examples

© 2009 EMC Corporation. All rights reserved. Physical Elements of CAS o Storage devices (CAS Based) oStorage node oAccess node oServers (to which storage devices get connected) oClient Server Private LAN Storage Nodes Access Nodes CAS System IP API

© 2009 EMC Corporation. All rights reserved. CAS Terminology oApplication Programming Interface (API) oA set of function calls that enables communication between applications or between an application and an operating system oBLOB (Binary Large Object) oThe actual data without the descriptive information (metadata) oThe Distinct Bit Sequence (DBS) of user data represents the actual content of a file and is independent of the filename and physical location API

© 2009 EMC Corporation. All rights reserved. CAS Terminology (Cont) oC-Clip oA package containing the user's data and associated metadata oC-Clip ID (C-Clip handle or C-Clip reference) is the CA that the system returns to the client application oContent Address (CA) oAn identifier that uniquely addresses the content of a file and not its location. Unlike location-based addresses, content addresses are inherently stable and, once calculated, they never change and always refer to the same content oC-Clip Descriptor File (CDF) oThe additional XML file that the system creates when making a C-Clip. This file includes the content addresses for all referenced BLOBs and associated metadata

© 2009 EMC Corporation. All rights reserved. API How CAS Stores a Data Object Unique Content Address is calculated Client presents data to API to be archived CAS System Client Application Server CDF C-Clip (Object) Object is sent to CAS System via CAS API over IP

© 2009 EMC Corporation. All rights reserved. API How CAS Stores a Data Object Unique Content Address is calculated Client presents data to API to be archived CAS System Client Application Server Object is sent to CAS System via CAS API over IP Object CAS System validates the Content Address and stores the object Acknowledgement returned to application Clip ID is retained and stored for future use

© 2009 EMC Corporation. All rights reserved. Application Server Client CAS System Object is needed by an application 1 CAS authenticates the request and delivers the object 4 Application queries the local table of C-Clip IDs, and locates the C-Clip ID for the Requested object. 2 Retrieval request along with the C-Clip ID is sent to the CAS System via CAS API over IP 3 How CAS Retrieves a Data Object API C-Clip ID

© 2009 EMC Corporation. All rights reserved. CAS Features oFeatures available with most CAS systems are: oIntegrity checking oData protection oLocal replication oRemote replication oLoad balancing oScalability oSelf-diagnosis and repair oReport generation and event notification oFault tolerance oThrough the use of redundant components and data protection schemes oAudit trails oDocumentation of management activities, access and disposition of data

© 2009 EMC Corporation. All rights reserved. Example 1: CAS Healthcare Solution oEach X-ray image ranges from about 15MB to over 1GB oPatient record is stored online for a period of days oBeyond 90 days patient records are archived Data Stored on CAS Patient Studies Stored locally for Short-Term Use (60 Days) Hospital CAS System Application Server API

© 2009 EMC Corporation. All rights reserved. Example 2: CAS Financial Solution oCheck image size is about 25KB oCheck imaging service provider may process 50–90 million check images per month oChecks are stored online for a period of 60 days oBeyond 60 days data is archived Bank CAS System Application Server API

© 2009 EMC Corporation. All rights reserved. Lesson Summary Key points covered in this lesson: oCAS architecture oPhysical and logical elements of CAS oCAS storage and retrieval process oCAS solution examples

© 2009 EMC Corporation. All rights reserved. Chapter Summary Key points covered in this chapter: oBenefits of CAS based storage strategy oOverview of physical and logical elements of CAS oStoring and retrieving data from CAS oCAS application examples

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