Evolution of Information Technology

Infrastructure

OEMBA Week 1

Definitions

IT Infrastructure: physical facilities, services and management that support computing resources Information Technology

HardwareSoftwareTelecommunications & NetworksDatabase

IT personnel

Definitions

Information Systems Architecture: the “plan” that aligns IT infrastructure with business needs Help people effectively fulfill their information

needs Note that the term “Information Architecture” is

now being used to describe process of designing web sites

Evolution of Information Technology Infrastructure

Data Processing Era

Micro-Computing Era

Network Era

1960

1980

1990

Ab

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Three Major Eras of the Computer Industry

Adapted from "Intranets and Middleware", HBR 397-118.

Mainframe

Mini/WAN

Client/Server

PC/LANdb

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Distributed

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Internet

Data Processing EraIT Infrastructure (legacy environment)

Hardware: Mainframe with host-centric processing

Software: Functional TPS, automation focus Database: Hierarchical or indexed files Telecommunications: very limited IT Personnel: technically oriented

Information Systems architecture? Labeled each application with Acronym and

mapped to functional area

Mainframe

Information Systems Architecture

Executive

Operations

Managerial

EIS

Functional Transaction Processing SystemsHierarchical Database

Management Information Systems

Functional IS

Transaction Processing System (TPS)

Emerged in the early days of IS Collect, store, and process transactions

Source documents are basis for input Perform routine, repetitive tasks Found in all functions of an organization If they fail, the whole organization may suffer

Efficiency Focus Automate “structured” decision processes

Mainframe

Management Information System (MIS)

Convert/use TPS data to support monitoring Alert managers to problems or opportunities Provide periodic and routine reports

e.g., summary reports, exception reports, comparison reports

“Information overload” Starting toward an effectiveness focus

Provide structured information to support decision making

Mainframe

Database Structures

Hierarchical Indexed sequential (hierarchical) approach Good for 1:M (parent-child) relationships Biggest advantage: Speed and efficiency of

search Problem:

Data relationships must be explicitly defined when database is created, difficult to change

Mainframe

Hierarchical Database

Mainframe

“Success” of IT systems?

Micro-Computing Era

IT Infrastructure (PC environment) Hardware: PCs Software: “Informating” Database: Functional Relational Telecommunications: low-speed Network: Local Area Networks IT Personnel: technically oriented

Information Systems architecture? End users creating own applications

PC/LAN

Information Systems Architecture

Executive

Operations

Managerial

EIS

Functional Transaction Processing SystemsRelational Database

Management Information Systems

SSS SSS SSS

Relational Database Approach

Advantage High flexibility – can easily combine information

from related tablesDisadvantage

Lower processing efficiency Expensive

Still “functional” focus

PC/LAN

Strategic Support Systems

Proliferation of desktop applications Decision Support Systems

Provide information to support “semi-structured” decision making

Simon’s model: Intelligence, Design, ChoiceAt least one of those stages is unstructured, and at least one

is structuredEffectiveness focus

“End-user” development Proliferation of localized supporting databases

PC/LAN

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Data Communications Hardware

Modem Modulate – demodulate

PC/LAN

Telecommunications Media

Criteria that determine speed: Frequency: cycles per second (baud). Hertz is one cycle

per second. measure of speed. (assume send one bit per cycle)

Bandwidth: difference between highest and lowest frequencies which can be transmitted. measure of capacity (pulse-code modulation)

Attenuation: signal strength weakens as it travels over distance.

Interference: EMI (electromagnetic) and RFI (radio frequency)

PC/LAN

Media

Twisted Pair: standard telephone lines High availability Lower speeds, poor security

Cable: coaxial cable. Less interference, higher bandwidth Higher cost, low security

PC/LAN

Wireless Media

Microwave Towers spaced 30 miles apart (line of sight) Easier than trenching wires into dirt Susceptible to interference

Satellite Eliminates line-of-sight issue Propagation delay

HF (high frequency)/RF (radio frequency) Use for short range (within warehouse)

PC/LAN

Methods to Direct Data

Circuit Switching Telephone Two-way connection established

PC/LAN

Local Area Network

Connects PCs together Peer-to-peer Server-based

File server

Distance restrictions Between 1000 and 5000 feet Why?

PC/LAN

LAN

Protocol Control line access and collision avoidance

Types -- broadcast Bus with CSMA/CD Token

Common LAN Protocols Ethernet: Bus with CSMA/CD Token Bus Token Ring

PC/LAN

Figure 6.4 The five main network typologies.

Figure 6.4 (Continued)

“Success” of IT Systems?

Client/Server Era IT Infrastructure (distributed computing

environment) Hardware: PCs and Servers Software: Facilitating Database: Distributed Relational and centralized

warehouse Telecommunications: high-speed Network: Client/Server, Distributed Middleware IT Personnel: technically skilled, business oriented

Information Systems architecture? Enterprise-wide applications

Client/Server

Types of Systems

Enterprise wide TPS (ERP)Corporate-wide Database

Sup Cus

Management Information Systems

Support Systems

Executive

Operations

Managerial

EIS

Specialized Support Systems

Office automation IS for “office” employees

Extension of “Office” Document tracking, communication, scheduling,

etc.

Client/Server

Specialized Support Systems (cont’d)

Expert Systems Knowledge-base integrated with DSS Most are “rule-based” systems that process facts,

not numbersCredit evaluationCisco tech support

Client/Server

LANs

New LAN Protocols Ethernet: Bus with CSMA/CD Token Bus Token Ring FDDI

Fiber Distributed Data InterfaceToken Ring on fiber

Fast Ethernet (100 mbps) Gigabit Ethernet

Client/Server

Actual Network Need to connect LANs

together Gateway

Translate protocols Bridge

Same protocol Router

Routes messages between same protocol

Switch Point-to-point

Hub Broadcast

Wide Area Network

What is it?How connect?

Leased Lines Satellite

Other options VAN

Private, data-only network managed by third party Virtual Private Network

Run WAN over internet (tunneling)

Client/Server

Wide Area Network – cont’dTypes of transmission

Circuit switching Packet switching Frame relay

Faster, less expensiveDoes not perform error correction

Asynchronous Transfer ModeSeamlessly and dynamically switch voice, data and

video at up to 2.5 GBPSUses uniform cells (53 by 8) eliminating need for

protocol conversion

Client/Server

Distributed Processing

Terminal-to-host All processing performed by host “Thin client”

File Server All processing performed by client

“Fat client” Server merely allows sharing of files

Client/Server Processing split between client and host

Client/Server

Database Approaches

Centralized All data in one location

Promotes maintenance and securitySubject to single point of failure

As size of database grew, performance sufferedBroadband still emerging, very expensive

Client/Server

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Database Approaches

Distributed data management Get data closer to applications Replicated

Complete copies in multiple locationsSignificant overhead

PartitionedEach location has portion of database

db

dbdb

dbClient/Server

Transactions used to interact with a relational “client-server” database For each transaction, OLTP typically deals with

a small number of rows from the tablesThe transactions are typically highly

structured, repetitive and have predetermined outcomes

E.g., orders, changing customer address, etc.

Online Transaction Processing

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dbdb

dbClient/Server

Network Era

IT Infrastructure (distributed computing environment) Hardware: PCs and Servers Software: Facilitating, enterprise-wide Database: Distributed Relational Telecommunications: high-speed Network: Middleware IT Personnel: still technical, but business

awareness

Client/Server

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Distributed

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High Speed Telecommunications ISDN

Worldwide digital protocol using existing twisted-pair telephone lines

Transmit voice, video and data up to 1.5 Mbps Dedicated Lines

T1 (1.5 Mbps) and T3 (45 Mbps) Asynchronous Transfer Mode (ATM)

Seamlessly and dynamically switch voice, data and videoSpeeds range from 155 Mbps to 2.5 Gbps

Uses uniform cells (53 by 8) eliminating need for protocol conversion

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Distributed

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Introduction of Middleware

Software that makes it possible for systems on different platforms to communicate with each other. Allows applications to talk to each other

Consistent Application Program Interface (API)Code application to talk to middleware, not

underlying resourcesUpgrade/modify underlying resources without

needing to modify applications

db dbdbdb

Client/Server

Middleware

Middleware Technologies

There were 3 basic types of middleware Transaction Processing Monitor (TP) Remote Procedure Call (RPC) Message-Oriented Middleware (MOM)

db dbdbdb

Client/Server

Middleware

Transaction Processing Monitor

(TP)

TP system:

Clients TP Monitor Data

Transaction request

Transaction Processing

db dbdbdb

Client/Server

Middleware

TP Monitor (cont’d)

TP is used to build on-line transaction processing (OLTP) systems by coordinating and monitoring the efforts of separate applications.

TP can provide the following: Control transaction applications Provide business logic/rules Database updates

db dbdbdb

Client/Server

Middleware

Remote Procedure Call (RPC)

Building distributed applications

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Client/Server

Middleware

Characteristics of RPC

Request/reply communicationSynchronous Vs Asynchronous

Location/platform transparencyAllows applications on separate machines to interact

without focusing on:The operating systemCommunications hardware & protocolProgramming language

db dbdbdb

Client/Server

Middleware

Message-Oriented Middleware (MOM)

Functions similar to RPCProvides asynchronous communication

between client & server applicationsThere are two types:

Publication/Subscription (Pub/Sub) Message Queuing

db dbdbdb

Client/Server

Middleware

Pub/Sub Vs. Message Queuing

Pub/Sub:

Message

Publishing Service

Subscribers

db dbdbdb

Client/Server

Middleware

Pub/Sub Vs. Message Queuing

(cont’d)

Message Queuing:

Queue

Message Receiving Application

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Client/Server

Middleware

DBMS Applications

With advent of high-speed, distributed architectures, expanded our use of database beyond capturing and storing transaction data Knowledge Discovery

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Distributed

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Knowledge Discovery

What is it: Process of extracting useful knowledge from

volumes of dataSupported by three technologies

Massive data collection Multiprocessor computing Data mining

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Distributed

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Massive Data Collection

Business problem: Difficult for larger organizations to analyze

organizational data from multiple sourcesEven with enterprise-wide applications, tend to have

distributed database Solution Data warehouse

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Distributed

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Data Warehouse

Collection of data in support of decision making process that is: Subject-oriented: organized by entity, not application Integrated: stored in one place, even though it originated

from a variety of sourcesCrosses functional boundaries of an organization

Time-variant: represents a snapshot at one point in time Nonvolatile: data is read-only Typically very large

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Distributed

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Issues with Traditional RDBMS as DW

Difficult for user to understand the DB structure and report information from it.

Slow retrieval due to complex relations

Tables

TablesTables

Tables

TablesTables

Tables Tables

Tables

Too Many Tables

Complex Links

Normalize Data

Multidimensional Database

OLTP not good when doing analysis of the database – poor performance

OLAP – on-line analytical processing Data stored in arrays – similar to tables Dimensions are the edges of the cube

Represent views of business data Sales Example: product, geography, time

Intersection represents sales of specific product, to customers in specific market, on certain date

Look for relationships among business elements in database – form basis for the “cubes”

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Distributed

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Advantages of OLAP

All hierarchical or aggregated values can be pre-calculated in the cube rather than accessing the Warehouse Major reduction in query time

Each cube makes “business sense” Not normalized data structures

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Distributed

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“Slice and Dice” an OLAP Cube

Multidimensional Database (cont’d)

Data marts Scaled-down version of a data warehouse that

focuses on a specific areae.g., a department, a business process

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Distributed

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Massive Data Analysis

Data mining Provides a means to extract patterns and

relationshipsExample: Analyze sales data to identify products that

may be attractive to a customerAmazon.com buyer suggestions

Two capabilitiesAutomated prediction of trends and behaviorsAutomated discovery of previously unknown patterns

Example: Shopping cart analysis

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Distributed

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Massive Data Analysis

Characteristics of Data Mining Relevant data in large database Typically has client/server architecture Tools integrated with spreadsheets to support

analysisData Mining Tools

Neural computing Intelligent agents Association Analysis

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Distributed

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IT Infrastructure (Web-enabled) Hardware: PCs, Servers, Browsers Software: Web extensions Database: Distributed Relational Network: Use IP-based standards Telecommunications: broadband IT Personnel: Business analysts, technical

specialties

Internet Era

Business use of the Internet:Electronic Commerce

E-business: Subset of e-commerce Transactions between

business partners

Individual EnterpriseSupplier/ CustomerInternet

Intranet

Extranet

B2C: InternetB2B: ExtranetB2E: Intranet

What is the Internet? Global network of LANs How did Internet evolve?

Originated in 1969, restricted to government, research and education (Arpanet)

WWW released in 1992 In 1993:

Ban on commercial use liftedMosaic released

Growth (different data depending on source)3 million in 9440 million in 97100 million in 98

What are the underlying technologies? Packet Switching

.X25 standard uses packets of 128 bytes Each packet travels independently through network

Protocols: TCP/IP Internet Protocol – destination address

Each computer has its own IP addressDomain name system (DNS)

Transmission Control Protocol – breaks information into data packets

Backbone

What is WWW? Application that uses the internet

Set a standards for storing, retrieving, formatting and displaying information via client/server architecture

HTML – standard language Connection

Uniform Resource Locator (URL) Hypertext transport protocol (http) – communication

protocol to transfer pages ftp: File Transfer Protocol

What are “Pull” and “Push” technologies?

Pull technology Individual browsers Offline browsers – retrieve at specified time Search engines

Metasearch engine – enter search in multiple engines

Push technology Pointcast – based on profile, sends pages Also used to distribute software updates

Filters: limit content

Broadband Communications High-speed connections

Distinguish “upstream” and “downstream”56K modem has upstream of 31.2 and downstream of 56

For Internet use, need higher downstream rates Three options:

DSL Cable Modem Satellite

Cable Modem

Send and receive data over the coaxial cable used in cable television system

Advantages of Cable ModemSpeed

The fastest home Internet connection speeds possibleUp to 30 mbps (megabits per second)

Ease of setup As simple as installing regular cable Call local provider for setup

Low cost AT&T@Home’s monthly service charge is

$39.95 in most markets

Disadvantage

Must have cableSpeed dependent on number of usersHigh installation fee

DSL - Digital Subscriber Lines

Brings high bandwidth information to homes or small businesses over ordinary telephone lines Can use telephone and PC on the same line and at

the same time

Advantages

Speed -- Individual connections will provide from 512

Kbps to 1.544 Mbps downstream and about 128 Kbps upstream

These are not shared (as in cable modem)Carries voice conversations and data

connections at the same time

Disadvantages

Restricted availabilityHigher cost for higher speeds

Satellite Technologies

A device used to transmit and receive signals from a satellite transponder

How does it work?

Advantages

Speed 400 Kbps downstream, upstream through modem

Internet and TV on one dishCan be used in remote areasEasy to install

Disadvantages

Slower than DSL or cable modem

Who controls access to consumer?

Cable Modem vs DSL Cable Industry: Cable modems

TCITime WarnerComcast

AT&TOwned cable reaching 25 million homesNow focusing on wireless

Baby BellsDigital Subscriber Lines

Web-based SolutionsEarly attempts to incorporate WWW into

inter-organizational systemsStatic, state-less web pages

Complicated navigation Not “connected” to underlying data

Page not dynamically updated when data changes

Object Request Broker (ORB)

Like RPC, ORB involves synchronous communication and location/platform transparency.

Unlike RPC, which uses standard programming methods, ORB uses object-oriented programming methods.

ORB (cont’d)Distributed objects

Object: encapsulate data and processes that affect dataExample: communicate with customer

Invoke “email” Two standards

Common Object Request Broker Architecture (COBRA)

Component Object Model (COM)

ORB (cont’d)

ORB architecture:

ORB

ClientRemote Service

(object)

locate service

activate service

establish connection

communicate

Advantages of ORB MiddlewareAnonymous interaction among applications

Integrate new client/server applications with existing legacy, mission-critical applications

Easier development environment Reduce cost Improve time-to-market of applications

Enables distributed data environmentEnables dynamic web applications

Disadvantages of ORB Middleware

Switching costs are high Upgrade from previous “Middleware” solutions

Requires high technical expertise Tend to outsource Lengthy deployment time

Unresolved Issues with ORB

SecurityScalability

Related to network capacityRapidly changing technologies

IT Infrastructure (Application Service Providers) Hardware: Web-based Servers, Browsers Software: Object-Oriented Database: Distributed Relational, XML Wrappers Network: Use IP-based standards Telecommunications: wireless IT Personnel: Business Partners, technical

specialties

Web Servicesdb dbdb

Web Services

Web Service Components

WS Directory

WS ClientWS Provider

XML/SOAP/HTTP

UDDIUDDI/W

SDL

db dbdb

Web Services

Dictionary: definewhat it is and how

it worksDirectory

Protocols for exchanging information

Web Service Components

WS Registry (UDDI, WSDL)

.Net

EnterpriseApplication

Enterprise Integration Server

(SOAP processor)

Secure TCP/IPConnections

SOAP/HTTP

Service Requests

J2EE

SOAP/H

TTP

SOAP/H

TTP

JDBC

ODBC

Web Services

ApplicationServer

db dbdb

Web Services

Wireless Application Protocol Web page display standard for PDAs

Distinguish WAN and LAN Multiple competing technologies for WAN

CDMA: code-division multiple accessGSM: global system for mobile communicationiDEN: ntegrated dispatch enhanced network, which is used by

NextelTDMA: time division multiple access (TDMA).

Each of these has their 2.5/3G track, and the acronyms will morph accordingly. For example, GPRS is the next evolution of GSM; 1X is the evolution of CDMA.

Wirelessdb dbdb

Web Services

Distinguish WAN and LAN (cont’d) Closer to standards for LAN

Wi-Fi: 802.11 families(b) – wireless ethernet. 11 mbps(a) – proposed standard. 54 mbps on 5 Gig radio band(g) – works in b band, but delivers a speed

BluetoothConnect devices to PC within 30 feet

Wirelessdb dbdb

Web Services

Summarize

“Internet” era Graphic-oriented, point-and-click, browser-based

applications Networks using IP-based standards

Company applications accessible via internet Applications developed to run on IP-based

networksProvides “market externalities” – large, lasting market

for application software, so developers willing to make significant investments

Summary – cont’d

Impact of current economic downturn? Delayed efforts to shift operations onto Internet Gartner Group: still expects B2B e-commerce to

reach $3.6 trillion by 2003