Module CC3002

Post Implementation IssuesLecture for Week 6

AY 2013 Spring

Support Issues

•What do we need from System Support?• IS Support Service: The Help

Desk• Service Level Agreements• Enhancement Request

Enhancement Requests

• Enhancement Requests–What are they?–How do they arise?–How are they managed?

• Help Desk’s role in Managing Enhancements• Information System evolution

What are ER

• An event that demonstrates the need of IS change generates enhancement requests• Also known as– Change requests–Modification request

Enhancement Requests

• Might arise from–Business Managers–Users–Designers–Programmers

Enhancement Requests

• Requests could include–Repost of Bugs–Features missing from the system–Ideas for future versions

Category

• Major changed triggered by –IS (strategic planning)–Requests from Business Managers

• Minor changes triggered by–Requests from user–Issues reported to Help Desk

Process

• User reports issues to Help Desk–User simply reporting problem–Not aware that enhancement

request has been triggered• Help Desk identified need for

Enhancement Request

Process

• Many issues resolved without changing IS–Some issues will require change in

software• Enhancement request is

generated–Defined procedure is followed

Managing Enhancement Requests

• Major changes–Trigger initiation of new project

• Project Life Cycle starts again–Conceptualization–Planning–Implementation–Completion

Managing Enhancement Requests

• Minor changes–Initiation of ‘mini’ project–Focus on area requiring change

• Immediate action to supply a fix –Known as Patch

Managing Enhancement Requests

Software Patch

An interim release ofPart of Information System

Intended to Address Deficiency inPrevious System

Managing Enhancement Requests

• Minor changes–Changes are bundled in with other

minor changes–Delivered in next maintenance

release of the system–Change request is rejected

Software Releases, Versions

• Major release–Will include many new features–Version number changes–Example 1.1 to 2.0

Software Releases, Versions

• Minor release may include–Some new features–Fixes a number of problems–Version number changes–Example 2.0 to 2.1

Software Releases, Versions

• Patch or Interim Release–Fixes one or more problems–Version number changes–Example 2.1 t0 2.11

Configuration Management

• Control of different versions of various software component (products) comprising an IS• Products may include Hardware,

OS, Software, Database

Configuration Management

The discipline of identifying components of continuously

evolving system for the purpose of controlling changes to these components and maintaining

integrity and traceability..Cadle and Yeates, 2001

Configuration Management

• Involves–Identifying changes to product–Controlling changes to product–Ensuring changes are made

properly–Reporting changes to others

Change Control

• Managing changes to an IS including–Impact analysis–Authorization–Documentation

Config Mgmt & Change Control

• Involves understanding of IS in–Dependency between different

components–Compatibility between versions of

components• Of Information System

Impact Analysis

• Before any change is authorized–Cost of required development work–Time required–Effect of change to user(s)–Effect of change to other parts of IS–Consequence of not implementing

change

Regression Testing

• After development work is completed• Before a change is installed

• Carry out appropriate regression testing

Regression Testing

• Testing program changes–Ensure that old code still works

with new changes• May be done by code testing

specialist

Regression Testing

• Coders develop code test scenario and exercises–Test new units of code written–Test cases from test bucket

Regression Testing

• Before a new version is released –Test bucket cases run against new

version–Make sure that all old capabilities

still function correctly

Regression Testing

• What could go wrong?–System might not work !–May introduce new errors in the

code–Might trigger unintended changes

elsewhere

IS Evolution

• New systems do not remain static• IS change over time• IS evolve in response to

environmental changes

IS Evolution

• Reasons for Evolution• (Problems with IS)• Poorly developed initial system–Requirement not met–Technical problems (bugs) in the

system

IS Evolution

• Reasons for Evolution• (Change in Environment)• Business Process Change• Changes in legislation• Technical environment change

IS Evolution

• Reasons for EvolutionSuccess

of Information System

Summary

• Enhancement requests• Configuration management• Change control• Impact analysis• Regression testing• IS evolution

Thanks Y

Thank You.