Introduction To The
New Mainframe
Stephen S. Linkin
Houston Community College
©HCCS & IBM® 2008 Stephen Linkin
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The New Mainframe
 Mainframe Computers Play A Central
Role In Daily Operations
 Coveted Place In Today’s E-business
Environment.

Banking, Finance, Healthcare, Insurance,
Public Utilities, Government
 Mainframe Computing Dominates Large-
Scale Business Computing.
©HCCS & IBM® 2008 Stephen Linkin
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The New Mainframe
 70% of all web pages are stored on
mainframe systems
 Transaction Processing is a Prime use.
©HCCS & IBM® 2008 Stephen Linkin
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The S/360: A Turning Point In
Mainframe History
 IBM 701 Circa 1951
 Univac System Circa 1950
 IBM 1401 Circa 1956
 IBM 360 Circa 1964
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The S/360: A Turning Point In
Mainframe History
 A Series Of Generations
First Generation Systems – 1951
 Second Generation – 1956
 Third Generation - 1964

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The S/360: A Turning Point In
Mainframe History
 Standardized Mainframe
Computers

Microcode
 Corrections
Or New Functions Can Be
Implemented By Updating
 No Concern Over Compatibility

Standardized Languages
 Assembler,
COBOL, FORTRAN, PL/1
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The S/360: A Turning Point In
Mainframe History
 Standardized Software Utilities
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An Evolving Architecture
 Definition Of Architecture
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An Evolving Architecture
 More And Faster Processors
 More Physical Memory And Greater
Memory Addressing Capability
 Dynamic Upgrading Of Hardware And
Software
 Automation Of Hardware Error Checking
And Recovery
©HCCS & IBM® 2008 Stephen Linkin
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An Evolving Architecture
 Enhanced (I/O) More And Faster Channels
 Sophisticated I/O Attachments, E.G. LAN
Adapters
 Ability To Divide Resources Of One Machine
Into Multiple, Isolated Systems, Running Its
Own OS
 Advanced Clustering, Parallel Sysplex, That
Share Data Among Multiple Systems.
©HCCS & IBM® 2008 Stephen Linkin
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An Evolving Architecture
 Stable
 Secure
 Compatible
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Mainframes In Our Midst
 Mainframes Are Largely Invisible
 They Are Resistant To Viruses And
Trojan Horses.
 They Share Space With Other Hardware
Devices:




External Storage Devices
Hardware Network Routers
Channel Controllers
Automated Tape “Robots”
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What Is A Mainframe?
The Largest Servers
 Server
Farms
Networked
Servers
Central Data Repository
 Platform
The Single Box…
©HCCS & IBM® 2008 Stephen Linkin
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What Is A Mainframe?
Style Of Operation
 Hosting
Commercial Databases
 Transaction Servers
 Applications Requiring A Great
Degree Of Security
©HCCS & IBM® 2008 Stephen Linkin
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What Is A Mainframe?
Style Of Operation
 Compatibility
 Centralized
Control Of
Resources
 Shared Access To Disk Drives
On Other Systems
©HCCS & IBM® 2008 Stephen Linkin
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What Is A Mainframe?
Style Of Operation
 Dedicated
Operations Staff
 S.O.P
Clustering Technologies
 Parallel
Sysplex
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Who uses mainframe
computers?
 Everyone




Perform large-scale transaction processing
(thousands of transactions per second)
Support thousands of users and application
programs concurrently accessing resources
Manage terabytes of information in databases
Handle large-bandwidth communication
 The roads of the information superhighway
often lead to a mainframe.
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Factors contributing to
mainframe use
 Reliability, Availability, Serviceability
 Security
 Scalabilty
 Continuing Compatibility
 Evolving Architecture
©HCCS & IBM® 2008 Stephen Linkin
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Factors contributing to
mainframe use
 Reliability, Availability, Serviceability
©HCCS & IBM® 2008 Stephen Linkin
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Factors contributing to
mainframe use
 Security
©HCCS & IBM® 2008 Stephen Linkin
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Factors contributing to
mainframe use
 Scalabilty
©HCCS & IBM® 2008 Stephen Linkin
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Factors contributing to
mainframe use
 Continuing Compatibility
©HCCS & IBM® 2008 Stephen Linkin
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Factors contributing to
mainframe use
 Evolving Architecture
©HCCS & IBM® 2008 Stephen Linkin
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Typical mainframe workloads
 Batch
 Interactive
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Typical mainframe workloads
 Batch
Fig 1-2



Large Volumes
Timed Activity
Multiple Tasks
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Typical mainframe workloads
 Interactive
Fig 1-3



Immediate
Short Response
Time
Mission Critical
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Roles in the mainframe world
 System Programmers
 System
Administrators
 Application Designers
And Programmers
 System Operators
 Production Control Analysts
©HCCS & IBM® 2008 Stephen Linkin
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z/OS and other mainframe
operating systems
 z/OS
 z/VM®
 z/VSE™
 Linux
 z/TPF
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z/OS and other mainframe
operating systems
 z/OS
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z/OS and other mainframe
operating systems
 z/VM®
©HCCS & IBM® 2008 Stephen Linkin
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z/OS and other mainframe
operating systems
 z/VSE™
©HCCS & IBM® 2008 Stephen Linkin
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z/OS and other mainframe
operating systems
 Linux
©HCCS & IBM® 2008 Stephen Linkin
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z/OS and other mainframe
operating systems
 z/TPF
©HCCS & IBM® 2008 Stephen Linkin
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Summary
 Read The Redbook
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