Lecture 4

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Auditing IT Governance Controls
Lesson Objectives
After studying this topic, you should:
• Understand the risks of incompatible functions
and how to structure the IT function.
• Be familiar with the controls and precautions
required to ensure the security of an organization’s
computer facilities.
• Understand the key elements of a disaster
recovery plan.
• Be familiar with the benefits, risks, and audit
issues related to IT outsourcing.
IT Governance
Information technology (IT) governance is a
relatively new subset of corporate governance
that focuses on the management and
assessment of strategic IT resources. Key
objectives of IT governance are to reduce risk
and ensure that investments in IT resources add
value to the corporation.
IT Governance Controls
This controls focus on:
1. Organizational structure of the IT function
2. Computer center operations
3. Disaster recovery planning
STRUCTURE OF THE
INFORMATION
TECHNOLOGY FUNCTION
• The organization of the IT function has
implications for the nature and effectiveness
of internal controls, which, in turn, has
implications for the audit.
Centralized Data Processing
Under the centralized data processing model,
all data processing is performed by one or more
large computers housed at a central site that
serves users throughout the organization.
Centralized Data Processing Approach
Org Chart of a Centralized IT Function
Related Terms
Database Administration
• Centrally organized companies maintain their
data resources in a central location that is
shared by all end users. In this shared data
arrangement, an independent group headed
by the database administrator (DBA) is
responsible for the security and integrity of
the database.
Data Processing
• The data processing group manages the
computer resources used to perform the dayto-day processing of transactions. It consists
of the following organizational functions: data
conversion, computer operations, and the
data library.
Data Conversion. The data conversion function
transcribes transaction data from hard-copy
source documents into computer input. For
example, data conversion could involve
keystroking sales orders into a sale order
application in modern systems, or transcribing
data into magnetic media (tape or disk) suitable
for computer processing in legacy type systems.
• Computer Operations. The electronic files
produced in data conversion are later
processed by the central computer, which is
managed by the computer operations groups.
Accounting applications are usually executed
according to a strict schedule that is controlled
by the central computer’s operating system.
Data Library. The data library is a room adjacent
to the computer center that provides safe
storage for the off-line data files. Those files
could be backups or current data files. For
instance, the data library could be used to store
backup data on DVDs, CD-ROMs, tapes, or other
storage devices.
Systems Development
• The information systems needs of users are
met by two related functions: system
development and systems maintenance.
• Systems Development is responsible for
analyzing user needs and for designing new
systems to satisfy those needs. The
participants in system development activities
include systems professionals, end users, and
stakeholders.
Systems professionals include systems analysts,
database designers, and programmers who
design and build the system. Systems
professionals gather facts about the user’s
problem, analyze the facts, and formulate a
solution. The product of their efforts is a new
information system.
• End users are those for whom the system is
built. They are the managers who receive
reports from the system and the operations
personnel who work directly with the system
as part of their daily responsibilities.
Stakeholders are individuals inside or outside
the firm who have an interest in the system, but
are not end users. They include accountants,
internal auditors, external auditors, and others
who oversee systems development.
Systems Maintenance
• Once a new system has been designed and
implemented, the systems maintenance group
assumes responsibility for keeping it current
with user needs. The term maintenance refers
to making changes to program logic to
accommodate shifts in user needs over time.
Segregation of Incompatible Functions
Operational tasks should be segregated to:
• 1. Separate transaction authorization from
transaction processing.
• 2. Separate record keeping from asset custody.
• 3. Divide transaction-processing tasks among
individuals such that short of collusion
• between two or more individuals fraud would
not be possible.
The Distributed Data Processing
• An alternative to the centralized model is the
concept of distributed data processing (DDP).
The topic of DDP is quite broad, touching
upon such related topics as end-user
computing, commercial software, networking,
and office automation.
• Simply stated, DDP involves reorganizing the
central IT function into small IT units that are
placed under the control of end users.
Risks Associated with DDP
1. Inefficient use of Resources
– risk of mismanagement of organization-wide IT
resources by end users
– risk of operational inefficiencies because of
redundant tasks being performed within the enduser committee
– risk of incompatible hardware and software
among end-user functions
2. Destruction of Audit Trails
3. Inadequate Segregation of Duties
4. Difficulty in Hiring Qualified Personnel
5. Lack of Standards
Advantages of DDP
1.
2.
3.
4.
Cost Control
Improved Cost Control Responsibility
Improved User Satisfaction
Backup Flexibility
Controlling the DDP Environment
Implement a Corporate IT Function
1. Central Testing of Commercial Hardware and
Software
2. User Services
3. Standard-setting body
4. Personnel Review
Audit Objective
The auditor’s objective is to verify that the
structure of the IT function is such that
individuals in incompatible areas are segregated
in accordance with the level of potential risk and
in a manner that promotes a working
environment. This is an environment in which
formal, rather than casual, relationships need to
exist between incompatible tasks.
Audit Procedures
If a company uses Centralized IT Function
• Review relevant documentation, including the current
organizational chart, mission statement, and job
descriptions for key functions, to determine if individuals
or groups are performing incompatible functions.
• Review systems documentation and maintenance
records for a sample of applications. Verify that
maintenance programmers assigned to specific projects
are not also the original design programmers.
• Verify that computer operators do not have
access to the operational details of a system’s
internal logic. Systems documentation, such as
systems flowcharts, logic flowcharts, and program
code listings, should not be part of the operation’s
documentation set.
• Through observation, determine that segregation
policy is being followed in practice. Review
operations room access logs to determine whether
programmers enter the facility for reasons other
than system failures.
If DDP is used:
• Review the current organizational chart,
mission statement, and job descriptions for
key functions to determine if individuals or
groups are performing incompatible duties.
• Verify that corporate policies and standards
for systems design, documentation, and
hardware and software acquisition are
published and provided to distributed IT units.
• Verify that compensating controls, such as
supervision and management monitoring, are
employed when segregation of incompatible
duties is economically infeasible.
• Review systems documentation to verify that
applications, procedures, and databases are
designed and functioning in accordance with
corporate standards.
THE COMPUTER CENTER
• Accountants routinely examine the physical
environment of the computer center as part
of their annual audit. The objective of this
section is to present computer center risks
and the controls that help to mitigate risk and
create a secure environment.
Physical Location
• The physical location of the computer center
directly affects the risk of destruction to a natural
or man-made disaster. To the extent possible, the
computer center should be away from humanmade and natural hazards, such as processing
plants, gas and water mains, airports, high-crime
areas, flood plains, and geological faults. The
center should be away from normal traffic, such
as the top floor of a building or in a separate, selfcontained building. Locating a computer in the
basement building increases its risk to floods.
Construction
• Ideally, a computer center should be located
in a single-story building of solid construction
with controlled access (discussed next). Utility
(power and telephone) lines should be
underground. The building windows should
not open and an air filtration system should
be in place that is capable of extracting
pollens, dust, and dust mites.
Access
• Access to the computer center should be
limited to the operators and other employees
who work there. Physical controls, such as
locked doors, should be employed to limit
access to the center. Access should be
controlled by a keypad or swipe card, though
fire exits with alarms are necessary. To achieve
a higher level of security, access should be
monitored by closed-circuit cameras and
video recording systems.
Air Conditioning
• Computers function best in an air-conditioned
environment, and providing adequate air
conditioning is often a requirement of the
vendor’s warranty. Computers operate best in
a temperature range of 70 to 75 degrees
Fahrenheit and a relative humidity of 50
percent. Logic errors can occur in computer
hardware when temperatures depart
significantly from this optimal range.
Fire Suppression
• Fire is the most serious threat to a firm’s
computer equipment. Many companies that
suffer computer center fires go out of business
because of the loss of critical records, such as
accounts receivable. The implementation of
an effective fire suppression system requires
consultation with specialists.
Fault Tolerance
• Fault tolerance is the ability of the system to
continue operation when part of the system
fails because of hardware failure, application
program error, or operator error.
• 1. Redundant arrays of independent disks
(RAID). Raid involves using parallel disks that
contain redundant elements of data and
applications. If one disk fails, the lost data are
automatically reconstructed from the
redundant components stored on the other
disks.
• 2. Uninterruptible power supplies.
Commercially provided electrical power
presents several problems that can disrupt the
computer center operations, including total
power failures, brownouts, power
fluctuations, and frequency variations. The
equipment used to control these problems
includes voltage regulators, surge protectors,
generators, and backup batteries.
Audit Objectives
The auditor must verify that:
• Physical security controls are adequate to
reasonably protect the organization from
physical exposures
• Insurance coverage on equipment is adequate
to compensate the organization for the
destruction of, or damage to, its computer
center
Audit Procedures
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Test of Physical Construction
Test of Fire Detection System
Test of Access Control
Rest of RAID
Test of Uninterruptible Power Supply
Test of Insurance Coverage
DISASTER RECOVERY
PLANNING
• Disasters such as earthquakes, floods,
sabotage, and even power failures can be
catastrophic to an organization’s computer
center and information systems. Disasters may
be natural, human-made or system failure.
Features of a DRP
•
•
•
•
1. Identify critical applications
2. Create a disaster recovery team
3. Provide site backup
4. Specify backup and off-site storage
procedures
Identify Critical Applications
• The first essential element of a DRP is to
identify the firm’s critical applications and
associated data files. Recovery efforts must
concentrate on restoring those applications
that are critical to the short-term survival of
the organization.
Create a Disaster Recovery Team
• Recovering from a disaster depends on timely
corrective action. Delays in performing
essential tasks prolongs the recovery period
and diminishes the prospects for a successful
recovery. To avoid serious omissions or
duplication of effort during implementation of
the contingency plan, task responsibility must
be clearly defined and communicated to the
personnel involved.
Provide Site Backup
• A necessary ingredient in a DRP is that it
provides for duplicate data processing
facilities following a disaster. Among the
options available the most common are
mutual aid pact; empty shell or cold site;
recovery operations center or hot site; and
internally provided backup.
• Mutual Aid Pact. A mutual aid pact is an
agreement between two or more
organizations (with compatible computer
facilities) to aid each other with their data
processing needs in the event of a disaster.
• Empty Shell. The empty shell or cold site plan
is an arrangement wherein the company buys
or leases a building that will serve as a data
center. In the event of a disaster, the shell is
available and ready to receive whatever
hardware the temporary user needs to run
essential systems.
• Recovery Operations Center. A recovery
operations center (ROC) or hot site is a fully
equipped backup data center that many
companies share. In addition to hardware and
backup facilities, ROC service providers offer a
range of technical services to their clients,
who pay an annual fee for access rights.
• Internally Provided Backup. Larger
organizations with multiple data processing
centers often prefer the self-reliance that
creating internal excess capacity provides. This
permits firms to develop standardized
hardware and software configurations, which
ensure functional compatibility among their
data processing centers and minimize cutover
problems in the event of a disaster.
Backup and Off-Site Storage
Procedures
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Operating System Backup
Application Backup
Backup Data Files
Backup Documentation
Backup Supplies and Source Documents
Test the DRP
Audit Objective
• The auditor should verify that management’s
disaster recovery plan is adequate and feasible
for dealing with a catastrophe that could
deprive the organization of its computing
resources.
Audit Procedures
The auditor may perform the following tests:
• Site Backup. The auditor should evaluate the
adequacy of the backup site arrangement.
System incompatibility and human nature
both greatly reduce the effectiveness of the
mutual aid pact.
• Critical Application List. The auditor should
review the list of critical applications to ensure
that it is complete. Missing applications can
result in failure to recover. The same is true,
however, for restoring unnecessary
applications.
• Software Backup. The auditor should verify
that copies of critical applications and
operating systems are stored off-site.
• Data Backup. The auditor should verify that
critical data files are backed up in accordance
with the DRP.
• Backup Supplies, Documents, and
Documentation. The system documentation,
supplies, and source documents needed to
process critical transactions should be backed
up and stored off-site.
• Disaster Recovery Team. The DRP should
clearly list the names, addresses, and
emergency telephone numbers of the disaster
recovery team members. The auditor should
verify that members of the team are current
employees and are aware of their assigned
responsibilities.
IT SOURCING
• The costs, risks, and responsibilities associated
with maintaining an effective corporate IT
function are significant. Many executives have
therefore opted to outsource their IT functions to
third-party vendors who take over responsibility
for the management of IT assets and staff and for
delivery of IT services, such as data entry, data
center operations, applications development,
applications maintenance, and network
management.
Risk Inherent to IT Sourcing
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Failure to perform
Vendor Exploitation
Outsourcing costs exceed benefits
Reduced Security
Loss of Strategic Advantage
Audit Implications of Sourcing IT
Functions
• An auditor should consider PSA 402, AUDIT
CONSIDERATIONS RELATING TO ENTITIES
USING SERVICE ORGANIZATIONS, in
conducting the audit of a client that
outsourced its IT functions
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