Class 3 AgendaClass 3 Agenda

ReviewReview

Data ManagementData Management

State St Bank CaseState St Bank Case

Text: Network EffectText: Network Effect

ReviewReview

Network Concepts Take-awaysNetwork Concepts Take-aways

IP Address ShortageIP Address Shortage

Data Management ConceptsData Management Concepts

Representing DataRepresenting Data Character SetsCharacter Sets Binary formatsBinary formats

Structured/Non-structured dataStructured/Non-structured data File SystemsFile Systems Storage Arrays and RAIDStorage Arrays and RAID Server Mass Storage MechanismsServer Mass Storage Mechanisms

Storage Area NetworksStorage Area Networks Network Attached StorageNetwork Attached Storage

Character SetsCharacter Sets

Representations of all text elementsRepresentations of all text elements ASCII – Standard for PC’s, unixASCII – Standard for PC’s, unix EBCDIC – The Mainframe EBCDIC – The Mainframe

alternativealternative UNICODE – The web standard: UNICODE – The web standard:

many more charactersmany more characters

Ascii Character Set Ascii Character Set ExampleExample(with Parity)(with Parity)

_ _ _ _ _ _ _ _1 1 1 0 0 0 0 1 = a

0 1 0 0 0 0 0 1 = A

0 0 1 1 0 1 0 1 = 5

Structured vs Non-Structured vs Non-structured Filesstructured Files DefinitionDefinition Impact on StorageImpact on Storage Impact on AccessImpact on Access Self-defining recordsSelf-defining records

File System Concepts and File System Concepts and IssuesIssues Storage: Blocks and SectorsStorage: Blocks and Sectors

Writing and cachingWriting and caching Fragmentation and re-organizationFragmentation and re-organization

Organization: File HierarchiesOrganization: File Hierarchies Folders, directories and qualifiers Folders, directories and qualifiers Inheriting and overriding properties Inheriting and overriding properties

Shared File SystemsShared File Systems Client SharingClient Sharing File ServersFile Servers

Shared Storage ArraysShared Storage Arrays

Level of abstraction / VirtualizationLevel of abstraction / Virtualization

Vendors: StorTek, IBM, EMC, HP, …Vendors: StorTek, IBM, EMC, HP, …

Goals: Management, flexibilityGoals: Management, flexibility

Issues: Connectivity, Security Issues: Connectivity, Security

Non-Storage Array ModelNon-Storage Array Model

svrA

svrB

svrC

disk1

disk2

disk3

Storage Array ModelStorage Array Model

svrA

svrB

svrC

disk1

disk2

disk3

D

I

S

K

A

RAID (redundant array of RAID (redundant array of independent disks) independent disks) RAID 0 (Striping)RAID 0 (Striping)

Consecutive blocks written to different disksConsecutive blocks written to different disks Performance gain onlyPerformance gain only

RAID 1 (Mirroring)RAID 1 (Mirroring) Writes all data to two separate drivesWrites all data to two separate drives Reads from either for performanceReads from either for performance

RAID 5 (Parity disk) RAID 5 (Parity disk) Any disk can fail without lossAny disk can fail without loss Parity drive allows failed drive to be Parity drive allows failed drive to be

recreatedrecreated

RAID 0 DiagramRAID 0 Diagram(Striping)(Striping)

Disk A

Disk B

Disk C

Disk D

Block1

Block2

Block3

Block4

RAID 1 DiagramRAID 1 Diagram(Mirroring)(Mirroring)

Disk A

DiskB

Block1

RAID 5 DiagramRAID 5 Diagram(with even Parity)(with even Parity)

Disk A

Disk B

Disk C

Disk D

ParityDisk

0 1 0 1 0

1 1 1 0 1

1 1 0 0 0

0 1 0 0 1

Advanced Data ManagementAdvanced Data Management

SYSTEM Managed StorageSYSTEM Managed Storage Multiple levels of accessMultiple levels of access Automatic promotion/demotionAutomatic promotion/demotion Catalog of “where”Catalog of “where” Merging of “backup” copiesMerging of “backup” copies

Master Data ManagementMaster Data Management On “Common functions” tier shared by On “Common functions” tier shared by

business applicationsbusiness applications Mechanism for sharing, requesting changesMechanism for sharing, requesting changes Resolves duplicates, ownership, domainsResolves duplicates, ownership, domains

Storage Area NetworksStorage Area Networks

““Fabric” connectivity between Fabric” connectivity between servers and storageservers and storage

Access is still via “owning” serverAccess is still via “owning” server Used for structured data, data Used for structured data, data

associated with specific applicationassociated with specific application Typically use specialized Typically use specialized

connectionsconnections

““Fabric” Storage Area Fabric” Storage Area NetworkNetwork

Server 1 Server 2 Server 3 Server 4

SAN Side 1 SAN Side 2

DiskA

DiskB

DiskC

Disk D

DiskE

Network-Attached StorageNetwork-Attached Storage

File systems accessed via internetFile systems accessed via internet Appear as remote drivesAppear as remote drives Used for unstructured data (e.g. Used for unstructured data (e.g.

documents), data used by many documents), data used by many servers servers

NAS DiagramNAS Diagram

Network

Server Server

NAS

State St. Bank: “A Higher Power”State St. Bank: “A Higher Power”

Distinguish “Governance” from Distinguish “Governance” from “Management”“Management”

Governance is necessary in every aspect of Governance is necessary in every aspect of business. Why is it singled out in IT/IS business. Why is it singled out in IT/IS management?management?

Why not take over and run the Deutsche Bank Why not take over and run the Deutsche Bank applications “as is”?applications “as is”?

What information is needed for proper What information is needed for proper decisions on a client? Who is responsible for decisions on a client? Who is responsible for that information?that information?

What type of planning and preparation What type of planning and preparation enhance “nimbleness”?enhance “nimbleness”?

HomeworkHomework

Mon: Text Chapter 4: Moore’s LawMon: Text Chapter 4: Moore’s Law

Wed: Case Study: Netflix (Chapter 3 Wed: Case Study: Netflix (Chapter 3 in Gallaugher)in Gallaugher)

Wed: Receive take home midterm Wed: Receive take home midterm exam (due next Monday)exam (due next Monday)