Carnegie Mellon University ©2006 - 2010 Robert T. Monroe 70-451 Management Information Systems IT Infrastructure 70-451 Management Information Systems

Carnegie Mellon University ©2006 - 2010 Robert T. Monroe 70-451 Management Information Systems

IT Infrastructure

70-451 Management Information Systems

Robert Monroe

September 1, 2010


After Today's Class You Should Be Able To:


Quick Review: IS Functions And Resources

Source: James O’Brien, Management Information Systems, 6th ed.


Computer Engineering in 5 Minutes!


Principle: Systems Are Built From Components

ChipsRAM

DisksPCB’s

OutputDevicesInput

Devices

Components IS Infrastructure

Server

Server

Server

SAN

Router

Firewall

PCPC

PCPC

PDA

…PDA

SmartCard

IT Devices

ChipsRAM

DisksPCB’s

OutputDevicesInput

Devices

Server


Binary Encoding: Computing With 0’s and 1’s

• Computers process binary representations of data – All data (and programs) encoded as sequences of 0’s and 1’s

• Examples:– Numbers: 101011

2 = 43

10

(1·32) + (0·16) + (1·8) + (0·4) + (1·2) + (1·1) = 43

– Letters: 01000001 (ASCII) = ‘A’ 01000010 (ASCII) = ‘B’

– Booleans: 0 = False1 = True

• Binary representations work well with digital electronics– Electrical current present → 1 – No electical current present → 0


Transistors and Logic Gates

• Transistors are digital switches that either block an electrical current or allow it to pass

• This property allows them to store state and implement Boolean Logic operations

• Transistors form the basis for modern microelectronics

• Logic Gates implement Boolean operations

AND Gate OR Gate NOT Gate(inverter)


Moore’s Law

Transistors Per Chip (1971-1989)

0

200,000

400,000

600,000

800,000

1,000,000

1,200,000

1,400,000

1971 1972 1974 1978 1982 1985 1989

Transistor density on integrated circuits doublesabout every two years.

- Gordon Moore, 1965


Moore’s Law




0

100,000,000

200,000,000

300,000,000

400,000,000

500,000,000

1989 1993 1997 1999 2000 2002 2003


Moore’s Law




0

100,000,000

200,000,000

300,000,000

400,000,000

500,000,000

1971

1972

1974

1978

1982

1985

1989

1993

1997

1999

2000

2002

2003


Implications of Moore’s Law

• The computing power that can be acquired for $X has approximately doubled every two years since 1965

• The cost of a given amount of computing power (Y) has fallen by approximately half every two years since 1965

• There is much debate about how long Moore’s law will continue to hold– It’s been declared dead many times before…

• There is also much debate whether it is less important now than it has been for the past two decades


It’s Not Just Integrated Circuits!

• Over the past decades there have also been exponential improvements in:– Random Access Memory (MB/$)– Hard disk drive capacity (MB/$)– Network bandwidth (MB/sec/$)

• Implications:– This industry dynamic should inform your hardware strategy– As the cost of computing power has plummeted, people

continue to apply IT to new, bigger, and harder problems– This trend is likely to continue


Hardware Components


Chips

• Integrated Circuits (ICs) are thin pieces of silicon with millions of transistors, arranged to perform specific computational tasks

• Microprocessors– A programmable general processing chip– The Central Processing Unit (CPU) of a computer is generally

a microprocessor

• Memory– Random Access Memory (RAM)– Read Only Memory (ROM)– Volatile vs non-volatile (flash)


Chips

• High fixed costs to produce a modern IC– Very expensive to design– Fabrication plants (fabs) can be

tremendously expensive

• Very low marginal costs– Driven primarily by yield

• Types of IC’s– Microprocessors, RAM, CCD

sensors, nano-tech, …

An IC schematic

A packaged microprocessor


Printed Circuit Boards

• Hold chips in place• Send power to chips• Route signals between chips• Route signals to external computing components• Examples:

– Motherboards

– Graphics cards

– Network Interface Cards

– Cellphone backplane


Connectors and Interfaces

• Connectors link electronic components together• Interfaces are the points where components meet• Common types of connectors:

– Printed Circuit Boards– System bus (built into motherboard, managed by chipset)– Cables

• Ethernet (Cat 5) -- label and pass around• USB – Universal Serial Bus• Firewire (IEEE 1394)• SCSI – Small Computer System Interface• Power• Video

– Network Interface Card


Power and Heat

• Electronic devices need power to operate

• Two common sources:– Power from the electric grid (plug it into the wall)

– Batteries

• Electrical usage generates heat

• Too much heat damages electronics

• Dispersing heat from electronic devices is critical

• Many technologies to do so– Heat sinks

– Airflow (fans)

– Liquid cooling


Storage

• Data storage is handled with many different types of devices in a Memory Hierarchy



Storage

• Primary storage– Registers on CPU– Processor cache– RAM

• On-line storage– Flash memory– Hard disk drives

• Near-line storage– CD-ROM, DVD-ROM– CD-RW/DVD-RW

• Off-line storage– Tape drives– Tape vaults– Tape bunkers (disaster recovery)



Storage Devices

Flash Memory

TapeCartridge

Hard Disk Drive (opened)

RAM


Measuring Storage Capacity and Performance

• Two basic units of measurement for storage– Capacity

• 1 Byte of data ≈ 1 character of storage (e.g. ‘a’)• MegaBytes (MB) – 1 MB ≈ 1 Million Bytes (≈ 1 minute of music)• GigaBytes (GB) – 1 GB ≈ 1 Billion Bytes (≈ 20 minutes DVD video)• Terrabytes (TB) – 1 TB ≈ 1 Trillion Bytes (≈ Google Earth Database)

– Access Speed • How fast can the processor retrieve the data from memory• Microseconds (μs) – 1 millionth of 1 second (10-6)• Milliseconds (ms) – 1 thousandth of 1 second (10-3)

• Another key metric for storage capability is how robust and fault tolerant the storage device is– Generally measured as Mean Time To Failure (MTTF)– Robustness is generally increased through redundancy


Software Components


Operating Systems

• An Operating System (OS) is software that handles the basic functions of a computer



Common Operating Systems

• There are many Operating Systems and OS vendors such as:

– Microsoft Windows (Windows 7, 2008 Server, Mobile, etc.)– Linus and UNIX (Sun Solaris, HP-UX, IBM AIX, etc.) – Mac OS X (Apple’s proprietary OS)

– Symbian (phone OS)– iOS (iPhone, iPad)– Google Android

– IBM OS/390 and z/OS (mainframes)– IBM OS/400 (common legacy midrange system)– DEC VAX (common legacy midrange system)

• Software applications are often written to a specific OS


Database Management Systems (DBMS)

• Database Management System software manages the capture, storage, organization, retrieval, and presentation of a company’s data

• Business Intelligence (BI) tools work with DBMS’s to help people analyze, visualize, and interpret the data stored in the underlying databases.

• We will study DBMS’s and BI tools in much greater detail later in the course


SCM, ERP, and CRM Systems

• … which we will discuss in detail next week


Communications Software

• Software to help people communicate, collaborate, and share information

• Examples?


Custom Applications

• Any software application written for a specific business (bespoke software)

• Often, much of the true business value that an information system creates comes from the custom applications created for it, or the systems integration work done to customize existing applications to work exactly the way that the business needs them to work

• What examples of high-value custom applications have we discussed in previous classes?


Building IT Devices from Components


Building IT Devices From Components


Server

Server

Server

SANFirewall

PCPC

PCPC

PDAPDA

SmartCard

IT Devices

ChipsRAM

DisksPCB’s

OutputDevicesInput

Devices

…

Operating System

ChipsRAM

DisksPCB’s

OutputDevicesInput

Devices

Server

Operating System NetworkMgmt Sys


Computer Categories: Client Systems


Computer Categories: Back-End Systems

• Servers– Built from (powerful) PC components– Generally located in controlled environment and accessed remotely– Designed to support multiple users, generally for dedicated tasks– Generally run a Unix variant (including Linux) or a MS Windows Server variant

• Mainframes– Very large computers designed to support hundreds of users concurrently– Emphasis on very, very high reliability and concurrent usage– Still a viable platform for some applications– Many, many legacy systems running on mainframes

• Midrange (mini) computers– Not widely used for new systems– Lots of legacy systems still running– Vax and HP are most common systems


Storage Systems• Storage systems provide large, shared repositories for data

• Advantages of a storage system include:– Shared data and storage space between computers– Higher reliability and availability than individual devices– Single point for administration and maintenance

• Disadvantages include:– Much higher cost per GB of storage (~ 3x to 100x the cost/GB)– More complex to configure and administer

• Common storage systems include:– RAID arrays– File servers– Network Attached Storage (NAS)– Storage Area Networks (SAN)


Dedicated Hardware Devices

• Mobile phones• Xbox 360, Wii, Playstation 3 • Flight simulators• Automotive informatics (nav systems, audio, etc…) • Factory control systems • Computer Numeric Control (CNC) machining tools• DVR’s and Satellite TV boxes


Networking


Common Networking Equipment

• Network Interface Cards (NICs) provide an interface from a computer to a network

• Hubs and switches concentrate connections from clients (computers) in a network

• Routers and Gateways form connections between networks (internetworking)

• Firewalls limit the types of connections a computer will accept from the network, and from whom it will accept them


Putting It All Together: Prototypical Network

Source: O’Brien, Management Information Systems, 6th ed.


Network Stacks

Source: O’Brien, Management Information Systems, 6th ed.

(TCP)

(IP)

(HTTP)


Constructing Information Systems Infrastructure From IT Devices


Putting It All Together: IS Infrastructure


Server

Server

Server

SANFirewall

PCPC

PCPC

PDAPDA

SmartCard

IT Devices

ChipsRAM

DisksPCB’s

OutputDevicesInput

Devices

…

Operating System

ChipsRAM

DisksPCB’s

OutputDevicesInput

Devices

Server

Operating System NetworkMgmt Sys


Putting It All Together: Systems Architecting

• Successful information system deployment and adoption requires an IT infrastructure that is:– Reliable (highly available)– Robust– Managable– Cost effective

• Achieving these goals requires careful planning, management, and investment

• This is the responsibility and role of a Systems Architect


Systems Architecting: Building Blocks

• Client machines– PC’s– PDA’s– Cell phones– Etc…

• Servers– File Servers– Web Servers– Mail Servers– Etc…

• Software– Operating systems– Web, application, e-mail servers– Network management systems

• Networking equipment– Firewalls– Routers– Gateways– Load Balancers

• Storage systems– File servers– RAID arrays– Storage Area Networks (SANs)– Network Attached Storage (NAS)

• Uninteruptable power supplies

• Heating, Ventilation, Cooling (HVAC)


Example: System Architecture Diagram


The Data Center

• A data center provides the technical physical infrastructure to run your web business


The Data Center


Data Centers Provide

• Core physical infrastructure– Power– HVAC– Fire prevention and suppression– Seismic monitoring and bracing– Physical security

• Hardware, networking, software infrastructure– Rack space– Networking infrastructure (big pipes, lots of ‘em)– Servers – Storage – Backup

• Management services (optional)– NOC


Managing IT Infrastructure: TCO

• Total Cost of Ownership is more important than purchase price.

• The cost to power, support, and update hardware devices over their useful lifetime often exceeds initial purchase price.

• Some challenges in building a hardware infrastructure include:– Understanding where your true costs of ownership lie – Identifying what is essential and what is not– Training and managing qualified personnel – Feed and caring (maintenance) of machines and network– Software licensing– Software and hardware obsolescence and upgrade cycles– Maintaining inventory (spares)– Power and HVAC


TCO Exercise:

• Write down five recurring expenses that an organization incurs in running a large information system in a data center.


Backup and Disaster Recovery

• Provided by data centers, specialists, or in-house

• Put together a plan for disaster scenarios– Evaluate cost of downtime– Devise plans to handle disasters– Plan DR strategy based on cost/benefit analysis

• Disaster Recovery Services– Data backup and storage (host-site, cold-site) – Data recovery and restoration– Business process fallback plans


Backup and Disaster Recovery

• How do you know how much to spend for backup? For disaster recovery?

• How do you decide how often to back up your organization’s data?


Network Operations Center (NOC)

A NOC provides:

• System monitoring

• Tech support calls

• On-site technicians

• Network security

• Platform admin

• Application admin


User Support Center (Help Desk)

• Everything to this point has focused on keeping the system running smoothly

• What about handling user problems?• There are analagous processes and procedures for

dealing with users– User support center (phones, e-mail, IM)

– Troubleshooting guides

– Processes for common requests

– Escalation procedures

– etc.


Strategic Question: Outsource Your Data Center?

Host Yourself:

• Better control

• Easier to update system quickly (Warning! Danger!)

• More expensive to do well than 3rd party hosting

• Much harder to build a robust data center yourself than to rent facility and expertise.

3rd Party hosting

• Quickly get a highly robust infrastructure

• No need to develop data center staff expertise

• Generally cheaper and easier overall than building yourself

• Loss of control – This can be both a blessing and

a curse


Recap: After Today's Class You Should Be Able To:


For Monday:

• Monday we will look at Customer Relationship Management Systems (CRM)

• More detailed information is available on the wiki– Readings will be up on wiki tomorrow

Documents

Carnegie Mellon University ©2006 - 2010 Robert T. Monroe 70-451 Management Information Systems IT Infrastructure 70-451 Management Information Systems