Chapter 4:
Systems Development &
Maintenance Activities
IT Auditing & Assurance, 2e, Hall & Singleton
PARTICIPANTS
 Systems professionals
 End users
 Stakeholders
 ACCOUNTANTS
 Internal
 External
 Limitations of involvement
IT Auditing & Assurance, 2e, Hall & Singleton
ACCOUNTANTS/AUDITORS
 Why are accountants/auditors involved?
 Experts in financial transaction processes
 Quality of AIS is determined in SDLC
 How are accountants involved?
 Users (e.g., user views and accounting
techniques)
 Members of SDLC development team
(e.g., Control Risk being minimized)
 Auditors (e.g., auditable systems)
IT Auditing & Assurance, 2e, Hall & Singleton
I.S. AQUISITION
 In-house development
 Purchase commercial
systems
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TRENDS IN COMMERCIAL
SOFTWARE
 Trends in commercial software
 Relatively low cost for general
purpose software
 Industry-specific vendors
 Businesses too small to have inhouse IS staff
 Downsizing & DDP
IT Auditing & Assurance, 2e, Hall & Singleton
TYPES OF COMMERCIAL
SYSTEMS
 Turnkey systems
 General accounting systems
 Typically in modules
 Special-purpose systems
 Example banking
 Office automation systems
 Purpose is to improve productivity
 Backbone systems (ERP)
 SAP, Peoplesoft, Baan, Movex
 Vendor-supported systems
 Hybrids
IT Auditing & Assurance, 2e, Hall & Singleton
COMMERCIAL SYSTEMS
 Advantages
 Implementation time
 Cost
 Reliability
 Disadvantages
 Independence
 Customization needs
 Maintenance
IT Auditing & Assurance, 2e, Hall & Singleton
SYSTEMS DEVELOPMENT LIFE
CYCLE (SDLC)
 New systems
1.
2.
3.
4.
5.
6.
7.
8.
Systems planning
Systems analysis
Conceptual systems design
System evaluation and selection
Detailed design
System programming and testing
System implementation
System maintenance
 SDLC -- Figure 4-1 [p.141]
IT Auditing & Assurance, 2e, Hall & Singleton
SYSTEMS PLANNING–
PHASE I
PURPOSE:
To link individual systems
projects to the strategic objectives of the firm.
 Link individual projects to strategic objectives of the
firm - Figure 4-2 [p.142]
 Who does it?
 Steering committee
 CEO, CFO, CIO, senior mgmt., auditors, external
parties
 Ethics and auditing standards limit when auditors
can serve on this committee
 Long-range planning: 3-5 years
 Allocation of resources - broad
IT Auditing & Assurance, 2e, Hall & Singleton
SYSTEMS PLANNINGPHASE I
 Level 1 = Strategic systems planning
 Why?
1. A changing plan is better than no plan
2. Reduces crises in systems development
3. Provides authorization control for SDLC
4. It works!
 Level 2 = Project planning
 Project proposal
 Project schedule
IT Auditing & Assurance, 2e, Hall & Singleton
SYSTEMS PLANNINGPHASE I
Auditor’s role in systems
planning
 Auditability
 Security
 Controls
IT Auditing & Assurance, 2e, Hall & Singleton
SYSTEMS PLANNINGPHASE I
SUMMARY
Identify user’s needs
Preparing proposals
Evaluating proposals
Prioritizing individual projects
Scheduling work
 Project Plan – allocates resources to specific
project
 Project Proposal – Go or not
 Project Schedule – represents mgmt’s
commitment
IT Auditing & Assurance, 2e, Hall & Singleton
SYSTEMS ANALYSISPHASE II
PURPOSE:
Effectively identify and analyze the
needs of the users for the new system.
Survey step
 Disadvantages:
 Tar pit syndrome
 Thinking inside the box
 Advantages:
• Identify aspects to keep
• Forcing analysts to understand the
system
• Isolating the root of problem symptoms
IT Auditing & Assurance, 2e, Hall & Singleton
SYSTEMS ANALYSISPHASE II
Gathering facts
Data sources
Users
Data stores
Processes
Data flows
Controls
Transaction volumes
Error rates
Resource costs
Bottlenecks
Redundant
operations
IT Auditing & Assurance, 2e, Hall & Singleton
SYSTEMS ANALYSISPHASE II
Fact-gathering techniques




Observation
Task participation
Personal interviews
Reviewing key documents
(see list, p. 147)
Systems analysis report
 Figure 4-3 (p.148)
Auditor’s role
 CAATTs (e.g., embedded modules)
IT Auditing & Assurance, 2e, Hall & Singleton
CONCEPTUAL SYSTEMS DESIGNPHASE III
PURPOSE: Develop alternative systems that
satisfy system requirements identified during
system analysis
1. Top-down (structured design)
[see Figure 4-4, p.150]



Designs general rather than specific
Enough details for design to demonstrate differences
Example: Figure 4-5, p. 151
2. Object-oriented approach (OOD)


Reusable objects
Creation of modules (library, inventory of objects)
3. Auditor’s role

special auditability features
IT Auditing & Assurance, 2e, Hall & Singleton
SYSTEM EVALUATION & SELECTION–
PHASE IV
PURPOSE: Process that seeks to identify the optimal
solution from the alternatives
1. Perform detailed feasibility study




Technical feasibility [existing IT or new IT?]
Legal feasibility
Operational feasibility
Degree of compatibility between the firm’s existing
procedures and personnel skills, and requirements
of the new system
Schedule feasibility [implementation]
2. Perform a cost-benefit analysis



Identify costs
Identify benefits
Compare the two
IT Auditing & Assurance, 2e, Hall & Singleton
SYSTEM EVALUATION & SELECTIONPHASE IV
Cost-Benefit Analysis: Costs
•
•
•
•
•
•
•
•
ONE-TIME COSTS:
Hardware acquisition
Site preparation
Software acquisition
Systems design
Programming
Testing
Data conversion
Training
RECURRING COSTS:
• Hardware maintenance
• Software maintenance
• Insurance
• Supplies
• Personnel
• Allocated existing IS
IT Auditing & Assurance, 2e, Hall & Singleton
SYSTEM EVALUATON & SELECTION–
PHASE IV
Cost-Benefit Analysis: Benefits
TANGIBLE:
• Increased revenues
• Increased sales in
existing markets
• Expansion into new
markets
• Cost Reduction 1
• Labor reduction
• Operating cost reduction
• Supplies
• overhead
• Reduced inventories
• Less expensive eqpt.
• Reduced eqpt. maint.
•
•
•
•
•
•
•
•
INTANGIBLE 2:
Increased customer
satisfaction
Improved employee
satisfaction
More current information
Improved decision making
Faster response to
competitors’ actions
More effective operations
Better internal and external
communications
Improved control
environment
IT Auditing & Assurance, 2e, Hall & Singleton
Cost-Benefit Analysis: Comparison
 NPV 1 [Table 4-4]
 Payback 2 [Figures 4-7a, 7b]
 BE
Auditor’s role
 Managerial accounting techniques 3
•
•
•
•
•
Escapable costs
Reasonable interest rates
Identify one-time and recurring costs
Realistic useful lives for competing projects
Determining financial values for intangible
benefits
IT Auditing & Assurance, 2e, Hall & Singleton
DETAILED DESIGN–PHASE V
PURPOSE: Produce a detailed description of the
proposed system that satisfies system
requirements identified during systems
analysis and is in accordance with conceptual
design.





User views
Database tables
Processes
Controls
i.e., a set of “blueprints”
IT Auditing & Assurance, 2e, Hall & Singleton
DETAILED DESIGN– PHASE V
Quality Assurance
• “Walkthrough”
• Quality assurance
IT Auditing & Assurance, 2e, Hall & Singleton
DETAILED DESIGN – PHASE V
Detailed Design Report
 Designs for input screens and source
documents
 Designs for screen outputs, reports, operational
documents
 Normalized database
 Database structures and diagrams
 Data flow diagrams (DFD’s)
 Database models (ER, Relational)
 Data dictionary
 Processing logic (flow charts)
IT Auditing & Assurance, 2e, Hall & Singleton
SYSTEM PROGRAMMING & TESTING–
PHASE VI
Program the Application
•
•
•
•
•
Procedural languages
Event-driven languages
OO languages
Programming the system
Test the application {Figure 4-8]
– Testing methodology
– Testing offline before deploying online
– Test data
• Why?
• Can provide valuable future benefits
IT Auditing & Assurance, 2e, Hall & Singleton
SYSTEMS IMPLEMENTATION–
PHASE VII
PURPOSE: Database structures are created and populated with
data, applications are coded and tested, equipment is
purchased and installed, employees are trained, the system
is documented, and the new system is installed.
 Testing the entire system
 Documenting the system



Designer and programmer documentation
Operator documentation
User documentation
• Novices
• Occasional users
• Frequent light users
• Frequent power users
• User handbook
• Tutorials
• Help features
IT Auditing & Assurance, 2e, Hall & Singleton
SYSTEMS IMPLEMENTATION–
PHASE VII
Conversion
 Converting the databases
 Validation
 Reconciliation
 Backup
 Converting the new system
Go live …
 Auditor involvement virtually stops!
 Cold turkey cutover
 Phased cutover
 Parallel operation cutover
IT Auditing & Assurance, 2e, Hall & Singleton
SYSTEMS IMPLEMENTATION–
PHASE VII
Post-Implementation Review
 Reviewed by independent team to
measure the success of the system
 Systems design adequacy [see list p. 170]
 Accuracy of time, cost, and benefit
estimates [see list p. 170]
 Auditor’s role





We’re back!!
Provide technical expertise
Specify documentation standards
Verify control adequacy
External auditors
IT Auditing & Assurance, 2e, Hall & Singleton
SYSTEMS IMPLEMENTATION–
PHASE VII
Auditors’ Role


We’re back!!
Provide technical expertise






Specify documentation standards
Verify control adequacy


AIS: GAAP, GAAS, SEC, IRS
Legal
Social / behavioral
IS/IT (if capable)
 Effective and efficient ways to limit application
testing
COSO – SAS No. 78 – PCAOB Standard #1
Impact on scope of external auditors
IT Auditing & Assurance, 2e, Hall & Singleton
SYSTEMS MAINTENANCE–PHASE VIII
PURPOSE: Changing systems to
accommodate changes in user needs
 80/20 rule 1
 Importance of documentation?
 Facilitate efficient changes
 Facilitate effective changes (at all!)
IT Auditing & Assurance, 2e, Hall & Singleton
Preliminary
Feasibility
Project
Authorization
Project
Proposal
Systems
Planning
Systems
Analysis
System
Analysis Rpt
Conceptual
Design
DFD
(general)
Systems
Selection
Detailed
Design
System
Implementation
Feasibility
Study
Detailed
Design Rpt
Post-Impl.
Review
DFD
(Detail)
ER
Diagram
Program
Flowcharts
Project
Schedule
System
Cost-Benefit
Selection Rpt
Analysis
Relational
Model
Documentation
IT Auditing & Assurance, 2e, Hall & Singleton
Normalized
Data
User
Acceptance Rpt
A materially flawed financial
application will eventually corrupt
financial data, which will then be
incorrectly reported in the financial
statements. Therefore, the
accuracy and integrity of the IS
directly affects the accuracy of the
client’s financial data.
IT Auditing & Assurance, 2e, Hall & Singleton
CONTROLLING & AUDITING THE
SDLC
Controlling New Systems
Development
 Systems authorization activities
 User specification activities
 Technical design activities
 Documentation is evidence of controls
 Documentation is a control!




Internal audit participation
User test and acceptance procedures
Audit objectives
Audit procedures
IT Auditing & Assurance, 2e, Hall & Singleton
CONTROLLING & AUDITING THE
SDLC
Audit Objectives & Procedures

Audit objectives
 Verify SDLC activities are applied consistently and in
accordance with management’s policies
 Verify original system is free from material errors and
fraud
 Verify system necessary and justified
 Verify documentation adequate and complete

Audit procedures






How verify SDLC activities applied consistently?
How verify system is free from material errors and fraud?
How verify system is necessary?
How verify system is justified?
How verify documentation is adequate and complete?
See page 174 for a list
IT Auditing & Assurance, 2e, Hall & Singleton
CONTROLLING & AUDITING THE
SDLC
Controlling Systems Maintenance
 Four minimum controls:




Formal authorization
Technical specifications
Retesting
Updating the documentation
IT Auditing & Assurance, 2e, Hall & Singleton
CONTROLLING & AUDITING THE
SDLC
Controlling Systems Maintenance
 Source program library controls




Why? What trying to prevent?
Unauthorized access
Unauthorized program changes
SPLMS [Figure 4-13, p. 177]
 SPLMS Controls




Storing programs on the SPL
Retrieving programs for maintenance purposes
Detecting obsolete programs
Documenting program changes (audit trail)
IT Auditing & Assurance, 2e, Hall & Singleton
CONTROLLING & AUDITING THE
SDLC
Controlled SPL Environment
 Password control
 On a specific program
 Separate test libraries
 Audit trail and management reports
 Describing software changes
 Program version numbers
 Controlling access to maintenance [SPL]
commands
IT Auditing & Assurance, 2e, Hall & Singleton
CONTROLLING & AUDITING THE
SDLC
Audit Objectives & Procedures
 Audit objectives
 Detect any unauthorized program
changes
 Verify that maintenance procedures
protect applications from unauthorized
changes
 Verify applications are free from material
errors
 Verify SPL are protected from
unauthorized access
IT Auditing & Assurance, 2e, Hall & Singleton
CONTROLLING & AUDITING THE
SDLC
Audit Objectives & Procedures
 Audit procedures
 Figure 4-14, p.179
 Identify unauthorized changes
 Reconcile program version numbers
 Confirm maintenance authorization
 Identify application errors
 Reconcile source code [after taking a sample]
 Review test results
 Retest the program
 Testing access to libraries
 Review programmer authority tables
 Test authority table
IT Auditing & Assurance, 2e, Hall & Singleton
Chapter 4:
Systems Development &
Maintenance Activities
IT Auditing & Assurance, 2e, Hall & Singleton
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