Chapter 7: Wireless, Mobile Computing, and Mobile Commerce
• Wireless is a term used to describe telecommunications in which electromagnetic waves (rather than
some form of wire or cable) carry the signal between communication devices (computer, PDAs, cell
• Mobile Computing refers to a real-time, wireless connection between a mobile device and other
computing environments, such as the internet or an intranet.
• Mobile Commerce (M-Commerce) refers to e-commerce (EC) transactions that are conducted in
wireless environment, especially via the internet.
• Pervasive Computing (Ubiquitous Computing) means that virtually every object has processing
power with wireless or wired connections to a global network.
• Wireless technologies include both wireless devices and wireless transmission media.
• Wireless devices are small enough to easily carry or wear, have sufficient computing power to perform
productive tasks and can communicate wirelessly with the Internet and other devices.
• Advantages of wireless device:
o Can make productive use of time that was formerly wasted (work in cars or public
o Work locations become much more flexible.
o Enable to allocate working time around personal and professional obligations.
• Wireless Application Protocol (WAP) is the standard that enables wireless devices with tiny display
screens, low bandwidth connections and minimal memory to access Web-based information and
• Microbrowsers are internet browsers with a small file size that can work within low-memory
constraints of wireless devices and the low bandwidths of wireless networks.
• Wireless Devices include pages, email handhelds, PDAs, cellular phones, and smart phones.
o Pager is a one-way, wireless messaging system; it alerts the user when it receives an incoming
o E-mail Handhelds, such as the BlackBerry, have a small display screen and a keypad for
typing short message. E-mail Handhelds help to keep in touch with clients and the office.
o Cell Phone use radio wave to provide two-way communication. The cell phone communicates
with radio antennas (towers) placed within adjacent geographic areas call cells. Cellular
technology, nowadays provides high transmission speeds and richer features (SMS, 3G, Video,
WWW), has progressed through four stages:
First generation (1G) – Analog signals and low bandwidth.
Second generation (2G) – Digital Signals for voice communication. Speed up to 10
2.5 G – Digital Signals for voice communication. Speed up to 144 Kbps.
Third generation (3G) – Digital Signals for voice communication. Speed up to 128
Kbps (in car), 384 Kbps (walking), and 2 Mbps (fixed).
o Personal Digital Assistants (PDAs) are small, handheld computers that can transmit digital
communications. PDAs provide electronic schedulers, address books, emails service,
wireless internet access, camera, and voice communication (some only).
o Smart Phones are a new class of digital communication appliances (color screen and built-
in keyboard) that combine the functions of PDA and digital cell phone. Smart phones
1 provide organizer, cell phone, digital camera, email, internet access, Short message service
(SMS), photo, music, and video.
• The smart camera phone can cause damage in workplace by easily send out company secrets.
• The major types of Wireless Transmission Media are Microwave, Satellite, Radio, and Infrared.
1. Microwave transmission systems are widely used for high-volume, long-distance, point-to-
point communication. Microwave towers usually cannot be spaced more than 30 miles apart
(earth surface’s not flat) and affected by bad weather such as heavy rain or snowstorms.
Point-to-point has two characteristics: first, the transmitter and receiver must be in view of each
other (called line-of-sight); and second, the transmission itself must be tightly directed from
transmitter to receiver.
2. Satellite transmission systems make use of communication satellites; three types of satellites,
each in a different orbit:
Geostationary earth orbit (GEO) orbits 22,300 miles directly above the equator
and maintains a fixed position; excellent for TV signals.
Medium-earth-orbit (MEO) are located 6,000 miles above the earth’s surface and
move; used for GPS and are less expensive.
Low-earth-orbit (LEO) are 400 to 700 miles above the surface and move much
quicker so they require many to have adequate coverage; use for telephone.
Footprint is the area of earth’s
surface reached by a satellite’s
transmission – overcomes the
limitations of microwave data relay
Broadcast transmission allows
satellites to send signals to many
receivers at one time.
Propagation delay is a brief pause in
transmissions from GEO satellites
which make two-way telephone
GPS is a wireless system that uses
satellites to enable users to
determine their position anywhere
on the earth; supported by 24 shared
Internet over Satellite (IOS) allows
users to access the Internet via GEO
satellites from a dish mounted on the
side of their homes. But2 only option
available in some areas and can have
a propagation delay or be disrupted
by environmental conditions. 3. Radio transmission uses radio-wave frequencies to send data directly between transmitters and
receivers. Satellite radio (digital radio) offers uninterrupted, near CD-quality music that is
beamed to your radio from space. (XM satellite radio uses GEO; Sirius uses MEO).
radio wave travel easily through normal walls
devices are cheap and easy to install
can transmit data at high speed
radio media can create electronic interference problems
radio transmissions are affected by similar equipment that operate on the same
4. Infrared light is red light that is not commonly visible to human eyes; common uses in remote
control units for TVs, VCRs, DVDs, CD players. Infrared are also used for short-distance
connection between computer and peripheral equipment and LAN.
Wireless Computer Networks and Internet Access:
• Advantages of Wireless networks:
o No line or cable connection needed
o Access more current data
o Small equipment, e.g. PDA
• Advantages of Wireless networks:
o Straight line signals: must be in range
o Network incompatibility
o Slower transmission (this is changing)
o Small screens/keyboards
o Less memory on PDAs
o High cost per minute, although this is changing
• Wireless manners: ‘Rules’ for using a wireless café:
o Limit your time
o Use cell phone quietly, headphones for music
o Minimize wall socket time
o Place cables in a safe place (ask permission to use extension cords)
o Clean and non-controversial surfing
• Institute of Electrical and Electronics Engineers (IEEE) standards for wireless computer networks
o IEEE 802.15 (Bluetooth) for wireless personal area networks (PANs) and 802.15.4 (Zigbee).
o IEEE 802.11 (Wi-Fi) for wireless local area networks (WLANs)
o IEEE 802.16 (Wi-Max) for wireless metropolitan area networks (WMANs)
o IEEE 802.20 (proposed) for wireless wide area networks (WWANs) – still under development.
• Impact of multiple standards:
o Difficult to exchange wireless information from different standards, e.g. BlueTooth to WiFi,
Cell phones to laptops
3 1. Bluetooth is used to create small wireless Personal area network (PAN) – a computer network used
for communication among computer devices (e.g., telephones, PDAs, smart phones) close to one
o can link up to 8 devices within a 10-meter area;
o uses low-power, radio-based communications;
o can transmit up to 1 Mbps.
Wireless phones, keyboards, computers, printers, and computing devices using Bluetooth can
communicate with one another without wires, e.g. keyboard – PC, headphone – cell phone.
2. Wireless Local Area Networks (WLAN) is like a wired LAN but without the cables; it requires a
transmitter with an antenna, called a wireless access point, which connects to a wired LAN or to
satellite dishes that provide an Internet connection.
o Hotspot a wireless access point that provides service to a number of users within a small
geographical perimeter (up to a couple hundred feet). Many cities are providing free hotspots.
o Wireless network interface card (NIC) is needed to communicate wirelessly and has a built-in
radio and antenna.
o IEEE standard for WLANs is the 802.11 family, known as Wi-Fi, for Wireless Fidelity.
o 802.11a can transmit up to 54 Mbps within 30 meters; 802.11b can transmit up to 11 Mbps
within 30-50 meters; 802.11g – 54 Mbps, 50 meters.
Benefits: + low cost and simple Internet access.
+ fast and easy internet access or intranet broadband (high-speed) access from public hotspots.
Problems: – Roaming: users cannot roam from hotspot to hotspot if the hotspots use different Wi-Fi
network services. Unless the service is free, each service has its own fees and separate
accounts for users to logon.
– Security: because Wi-Fi uses radio waves, it is difficult to protect.
– Cost: Although Wi-Fi services are low cost, many experts question whether commercial
Wi-Fi services can survive when so many free hotspots are available to users.
3. Worldwide Interoperability for Microwave Access (WiMax) is the name for IEEE standard 802.16.
WiMax antennas can transmit broadband Internet on sections to antennas on homes and businesses
miles away. WiMax can therefore provide long-distance broadband wireless access to rural areas and
other locations that are not currently being served.
○ WiMax has a wireless access range of up to 31 miles (Bluetooth 30 feet | Wi-Fi 300 feet)
○ Data transfer rate of 75 Mbps;
○ Secure system that offers voice and video.
• Mobile computing refers to real-time, wireless connection between a mobile device and other
computing environments, such as the Internet or an intranet and have 2 major characteristics that
differentiate it from other forms of computing.
1. Mobility – users carry a mobile device and can initiate a real-time contact with other systems
from wherever they happen to be.
2. Broad reach – users can be reached instantly when they carry an open mobile device.
• The 2 characteristics, mobility and broad reach, create five value-added attributes that break the barriers
of geography and time:
1. Ubiquity – Provide information and communication regardless of the user’s location.
2. Convenience – Easy and fast to access the Web and intranets without booting up a PC.
3. Instant connectivity – Easy and fast to access the Web and intranets without booting up a PC.
4. Personalization –Information can be customized and sent to individual consumers as an SMS.
4 5. Localizations of products and services – Knowing a user’s physical location helps a company
advertise its products and services.
• Mobile Commerce (M-commerce) refers to e-commerce (EC) transactions that are conducted in a
wireless environment especially via the Internet.
• The development of m-commerce is driven by the following factors:
o Widespread availability of mobile devices – number of cell phone (internet access) increase
o No need for a PC
o The “Cell phone culture” – the widespread use of cell phone
o Declining prices of wireless service
o Bandwidth improvement – faster (Wi-Fi and Wi-Max) and richer features (Voice, image,
• Mobile computing could provide the following benefits:
o Virtual organizations – organizations exist that do not have a physical office location
o Virtual desk or working from multiple locations
o We could be “traveling salespeople” or work from home?
o You can wear clothing and equipment that monitors your heart rate, step cadence and more!
• Wireless computing may have the following problems:
o How would you feel about being accessible to your employer all the time?
o Would you take your laptop to a restaurant, or do you go to a restaurant to socialize?
o Blurring of work and leisure is occurring.
• Mobile Commerce Applications:
○ Financial Services
Mobile Banking – Using banking services on their cell phone.
Wireless Electronic Payment Systems – can buy goods or service through cell phone
Micropayments – small purchase amount, e.g. using phone pay for taxi or transit fare
Mobile (Wireless) Wallets – E.g. Nokia wallet store credit card numbers in phone for
Wireless Bill Payments – company allows customer to pay bill directly from cell phone
○ Intrabusiness Application – Most of today’s m-commerce applications are used within
organizations. Mobile service can be used to assist in assign jobs to mobile employees, along
with information about tasks.
○ Accessing Information – The portals provide information anywhere and anytime to users.
Mobile Portal aggregates and provides content and services for mobile users that
include news, sports, email, entertainment, travel and restaurant information; community
services; and stock trading.
Voice Portal is a Web site with an audio interface and can also be accessed through a
standard or cell phone. E.g. Weather, current traffic, or reminder calls.
○ Location-based Applications – As in e-commerce, M-commerce B2C applications are
concentrated in three major areas: retail shopping, advertising, and providing customer service.
Shopping from Wireless Devices – online vendors allow customers to shop from
Location-based Advertising is when marketers know the current locations and
preferences of mobile users, they can send user-specific advertising messages to wireless
devices about nearby shops, malls and restaurants.
5 Location-based Services provide information to customers about local services and
conditions via cell phones, such as taxi service, gas station, hotels, and restaurants.
○ Wireless Telemedicine is the use of modern telecommunications and information technologies
for the provision of clinical care to individuals located at a distance and for the transmission of
information to provide that care.
Storing and transferring digital images from one location to another.
Allowing a patient in one location to consult with a medical specialist in another in real
time through videoconferencing.
Using robots to perform remote surgery, in most cases, the patient is in a rural area and
the specialist is in an urban area.
Wireless technology has advanced the ways in which prescriptions are filled.
Mobile communications has provided a valuable telemedicine application for emergency
situations that arise during airplane flights.
○ Telemetry is the wireless transmission and receipt of data gathered from remote sensors.
Technicians can use telemetry to identify maintenance problems in equipment;
Doctors can monitor patients and control medical equipment from a distance;
Car manufacturers use telemetry for remote vehicle diagnosis and preventive
• Pervasive Computing (Ubiquitous computing) is invisible “everywhere computing” that is embedded
in the objects around us – the floors, the lights, our cars, washing machine, microwave oven, cell
phones, clothes, and so on. (e.g., smart home, smart appliances)
o Radio-Frequency Identification (RFID) Technology allows manufacturers to attach tags with
antennas and computer chips on goods and then track their movement through radio signals.
RFID was developed to replace bar codes, Universal Product Code (UPC) – 12 digits (2
present country, 4 present manufactory, 6 assigned by manufacturer). Bar codes have
limitations: a) They requires scanning device; b) Printed on paper can be ripped or lost,
and c) Bar code identifies the manufacturer and product, but not the item.
Auto-ID creates a network that connects computers to objects, an Internet of “things”.
This Internet of things will provide the ability to track individual items as they move
from factories to store shelves to recycling facilities. This will make possible near-
pervfect supply chian visibility.
RFID systems use tags with embedded microchips, contain data, and antennas to
transmit radio signals over a short distance to RFID readers. RFID tags contains
information about item such as its location, where and when it was made.
The problem with RFID is expensive because RFID tags cost 10-50 cents for each
Uses for RFID:
Tolls on highways
Embedded in merchandise to prevent theft
Attached to merchandise for tracking shipment and receipt
Embedded in a person or animal for identification
o Wireless Sensor Networks (WSNs) are networks of interconnected, battery-powered, wireless
sensors called motes that are placed into the physical environment. WSNs can be used to better
understand environment (biology), enhances security by detecting intruder, or in business to
understand storage environment of organic goods.
6 Motes collect data from many points over an extended space. Each mote contains
processing, storage, and radio frequency sensors and antennaes. Motes provide
information that enables a central computer to integrate reports of the same activity from
different angles within the network.
A new type of WSNs is Mesh Network – composed of motes, where each mote wakes
up for a fraction of a second when it has data to transmit and then relays that data to its
An advantage is if one mote fails, another one can pick up the data.
Very efficient and reliable.
If more bandwidth is needed, it is easy to boost performance by placing new
motes when and where they are required.
One kind of Mesh Network is Zigbee – targets applications that need low data
transmission rates and low power consumption:
moves data only one-fourth as fast as Bluetooth;
Can handle hundreds of devices at once;
most promising application is meter reading.
Current focus is to wirelessly link sensors that are embedded into industrial controls,
medical devices, smoke and intruder alarms and building and home automaton.
• Wireless Security: Wireless networks present huge challenge to management because of lack of
security. There are four major threats of wireless networks:
o Rogue access point is an unauthorized access point to a wireless network.
It could be harmless – set up by employees but fails to tell IT department
It could be harm or serious problem: “Evil Twin” – the attacker creates wireless access
point with the same wireless network name, or SSID, as the one that authorized users
expect. The attackers can serve them a Web page asking for them to provide confidential
information such as user names, passwords, and account numbers.
○ War driving is the act of locating WLANs while driving around a city or elsewhere. If a
WLAN has a range that extends beyond the building, attackers can intrude into the network and
obtain a free internet or unauthorized access to important data or resource.
○ Eavesdropping refers to efforts by unauthorized users to try to access data traveling over
○ RF (Radio frequency) jamming is when a person or a device intentionally or unintentionally
interferes with your wireless network transmissions.
• To avoid those previously mentioned threats implement the following solutions:
o Detect unauthorized access points with devices from NetStumbler;
o Block your SSIDs (the name of your wireless network) because they let war drivers know a
wireless network is present.
o Encrypt wireless transmissions with Wi-Fi Protected Access (WPA). To gain access to
WPA-encrypt information, users enter a virtually unbreakable password.
o Always know who is using your network and what they are doing on it. Limit access to
approved devices, give authorized users access only to the service you allow. E.g., allow client
to use internet but not your company intranet.
o Implement a system that automatically shifts to a different wireless channel when there is
interference or when one point is jammed.
• Security of Mobile Technology
7 o High-security calls should not be made from a cell phone
o Use approved cryptography solutions
o Use difficult to guess passwords
o Change passwords often
o Use anti-virus software
8 Chapter 10: Managing the Acquisition of Information Technology
• Organizations must analyze the need for the IT application. Each IT application must be justified in
terms of costs and benefits.
• Application portfolio is a prioritized list of both existing and potential IT applications of a company;
• IT Planning: The planning process for new IT applications begins with analysis of the organizational
strategic plan. Organizational strategic plan states the firm’s overall mission, the goals that follow
from that mission, and the broad steps necessary to reach these goals. IT architecture delineates the
way an organization’s information resources should be used to accomplish its mission. The
organizational strategic plan and the existing IT architecture provide the inputs in developing the IT
o IT strategic plan is a set of long-range goals that describe the IT infrastructure and major IT
initiatives needed to achieve the goals of the organization. It must meet 3 objectives:
It must be aligned with the organization’s strategic plan
It must provide for an IT architecture that enables users, applications and databases to be
seamlessly networked and integrated.
It must efficiently allocate IT development resources among competing projects, so that
projects can be completed on time and within budget and the have the required
o IT Operational Plan consists of a clear set of projects that the IT department and functional
area managers will execute in support of the IT strategic plan; contains the following elements:
Mission – derived from IT strategy.
IT environment – summary of information needs of the functional areas and of the
organization as a whole.
Objectives of the IT function – best current estimate of the goals.
Constraints of the IT function – technological, financial, personnel and other resource
Application portfolio – prioritized inventory of present applications and a detailed plan
of projects to be developed or continued.
Resource allocation and project management – listing of who is going to do what, how
9 • Evaluating & Justifying IT Investment: Benefits, Costs & Issues: Justify investment includes 3
functions: assessing the costs, assessing the benefit (value), and comparing the two.
o Assessing the costs:
Fixed costs: are those costs that remain the same regardless of change in the activity
level. For IT, fixed costs include infrastructure cost, cost of IT services, and IT
The cost of a system does not end when the system is installed, i.e. cost for maintaining,
debugging, and improving the system can accumulate over many years.
Total cost of ownership (TCO): Formula for calculating cost of acquiring, operating
and controlling an IT system.
o Assessing the benefits (Values)
Intangible benefits. Benefits from IT that may be very desirable but difficult to place an
accurate monetary value on. E.g. improve customer or partner relations or improve
o Comparing the two: conduct the Cost-Benefit Analysis
• Conducting the Cost-Benefit Analysis: Four common approaches:
1. Net Present Value (NPV): Using the NPV method, analysts convert future values of benefits to
their present-value equivalent by discounting them at the organization’s cost of funds. The can
compare the present value of the future benefits to the cost required to achieve those benefits
and determine whether the benefits exceed the costs. NPV method works well when cost and
benefit can be converted into monetary values (tangible).
Income by IT Investment
2. Return on investment (ROI) =
Cost of IT Investment
It measures the effectiveness of management in generating profits with its available assets. ROI
measures in a percentage, the higher the percentage return, the better ROI.
3. Breakeven Analysis determines the point at which the cumulative dollar value of the benefits
from a project equals the investment made in the project.
4. The business case approach. A business case is a written document that managers use to justify
funding one or more specific applications or projects. Its major emphasis is the justification for
a specific required investment, but it also provides the bridge between the initial plan and its
execution. Its purpose is not only to get approval and funding, but also to provide the foundation
for tactical decision making and technology risk management.
• Recognition of a need or problem
o New services may be required for customers
o There may be a need to keep up with the competition
o Government regulations, changing business conditions or simply the passage of time may
result in the need for massive changes
10 • Strategies for Acquiring IT Applications: Four major options for acquiring IT applications: Buy the
applications (off-the-shelf approach), Lease the applications, Developing the applications in-house
(Insourcing), and outsource them.
1. Buy the Applications (Off-the-Shelf Approach) – Buy existing commercial software
2. Lease the applications – Compared with the buy option and the option to develop application
in-house, the “ lease” option can save a company both time and money. Like buy option, leased
packages may not always exactly fit the company’s needs. However, vendor software generally
includes most commonly needed features by company in a given industry.
Small-to-medium-size enterprises (SMEs) choose to least applications because they
cannot afford the major investment in IT software.
Larger company may decide to least applications to test potential IT solutions before
heavy investments, or because they want to quickly response to the market and cannot
afford the long-wait for in-house application developing process.
3. Developing the applications in-house (Insourcing) – usually requires more time-consuming
and more costly than buying or leasing, but it leads to a better fit with the specific organizational
needs. In-house development is a challenging task for several reason: 1) many applications are
proprietary, 2) many people from outside the organization use these applications, and 3) these
application involve multiple organizations. In-house development can make use of various of
methodologies: SDLC, prototyping, joint application development, rapid application
4. Outsourcing Applications – Acquiring IT applications from outside contractors or external
11 Methodology to Develop the Application In-House (Insourcing)
• Software Development Life Cycle (SDLC) is the traditional systems development method that
organizations use for large-scale IT projects. SDLC processes are systems investigation, systems
analysis, systems design, programming, testing, implementation, operation and maintenance.
Waterfall approach is when tasks in one phase are completed before the work proceeds to the next
stage. Today, however, design tools allow for greater flexibility.
o Major advantages of SDLC:
Error detection and error prevention – save money in long run
o Major disadvantages
Time-consuming and expensive
Discourages changes once user requirements are done
○ Development Teams include:
Users – employees from all functional areas and levels of company who interact with
the system, either directly or indirectly.
Champion or Sponsor– employees chosen from each department to train first, then they
can become the super users to teach others.
System Analysts – information system professionals who specialize in analyzing and
designing information systems.
Programmers – information systems professionals who modify existing computer
programs or write new computer programs to satisfy user needs.
Technical Specialists – experts on a certain type of technology, such as database or
o Systems Stakeholders are people who are affected by changes in information systems. All
stakeholders are typically involved in varying degrees and at various times in system
o User involvement:
Feedback must be truly considered and honestly responded to
User involvement does not mean that all suggestions will be implemented
Management needs to encourage and provide adequate resources
User involvement needs to occur during ALL development phases
o Examples of user involvement
Identifying problems with existing systems
Suggesting ways problems can be solved
Identifying the type of data that needs to be kept and how it is to be processed
Approving the request for proposal
Being on the testing team, or designing tests
Helping to train other users
Providing suggestions for maintenance or enhancements
12 The Eight-stage Systems Development Life Cycle (SDLC):
1. Systems Investigation – Begins with the business problem (or opportunity) followed by the feasibility
Feasibility study analyzes which of the three solutions best fits the particular business problem:
1) do nothing and continue to use the existing system unchanged, 2) modify or enhance the
existing system, or 3) develop a new system. Feasibility study is important because it can
prevent organizations from making costly mistakes.
− Technical feasibility determines whether hardware, software and communications
components can be developed and /or acquired to solve a business problem.
− Economic feasibility: determines whether a project is an acceptable financial risk and if
the organization can afford the expense and time needed to complete it.
− Behavioral feasibility: Assessment of the human issues involved in a proposed project,
including resistance to change and skills and training needs. People generally fear
change. Employees may ‘fight’ a new system, some may leave the organization. Change
could be seen as threatening rather than as a challenge, so the key is being given time to
talk and to learn.
− Organizational feasibility: Organization’s ability to access the proposed project. E.g.
legal or other constrains, conflicts with strategic plan.
Go/No-Go Decision: Go – proceeds the project and start system analysis. No Go – reject or
wait until better conditions.
2. Systems Analysis is the examination of the business problem that the organization plans to solve with
an information system.
Main purpose is to gather information about existing system to determine requirements for the
new or improved system, i.e., system requirements. Systems analysts may gather information
requirements by interviews with users, direct observation, and document analysis.
Problems with gathering information requirements: 1) business problem may be poorly defined;
2) users may not know exactly what the problem is, what they want, or what they need; 3) users
may disagree with one another about business procedures or even about the business problems;
4) the problem may not be information related, i.e. nothing to do with IT, e.g. management
13 System Analysis produces 1) strengths and weaknesses of the existing system, 2) functions that
the new system must have to solve the business problems, and 3) user information requirements
for the new systems.
3. Systems Design describes how the system will accomplish the tasks to solve the business problem.
This steps is about technical design that specifies:
− Security requirements, System outputs (reports), inputs, user interfaces, data structures
− Hardware, software, databases, telecommunications, personnel & procedures;
− Blueprint of how these components are integrated.
Logical system design states what the system will do, using abstract specifications. E.g. design
of WAN that connect the company plants.
Physical system design states how the system will perform its functions, with actual physical
specifications. E.g. specify communication hardware (PC and routers), software (Network
Operating Systems), media (fiber optics or satellite), and bandwidth (100 Mbps).
Scope creep is caused by adding functions after the project has been initiated due to better
understanding of system and change in business conditions. Scope creep often creates more cost
and delay the schedule of a project.
4. Programming involves the translation of a system’s design specification into computer code.
5. Testing check to see if the computer code will produce the expected and desired results under certain
conditions. Testing may be done by programmers, quality assurance personnel or users.
Testing is designed to delete errors (bugs) in the computer code. These errors are of two types.
Syntax errors (e.g., misspelled word or a misplaced comma) and logic errors that permit the
program to run but result in incorrect output. Logic errors are more difficult to detect.
Complex software can not avoid error, so “good-enough” software is often acceptable when
they meet the functional objectives and not affect the system’s performance.
6. Implementation or deployment is the process of converting from the old system to the new system.
Organizations use four major conversion strategies; parallel, direct, pilot and phased.
Parallel conversion – The process that the old system and the new system operate at the same
time for a period of time, and compare the outputs. It’s the most expensive but the least risk,
often use with very large systems.
Direct conversion (or cut-over) – The process that the old system is cut off and the new system
turned on at a certain point in time. It’s the least expensive but the most risk. It’s rarely used.
Pilot conversion – The process that introduces the new system in one part of the organization
on a trial basis, such as in one function areas, when new system is working property, it is
introduced in other parts of the organization.
Phased conversion – The process that introduces components of the new system, such as
individual modules, in stages. If one works properly, then other modules are introduced until the
entire new system is operational. E.g. for accounting, AR first, then payroll … AP, etc.
Management style affects success: Management styles observed during the implementation of an
automated working paper system: Indifferent autocrat, Benevolent autocrat, Participative manager.
7 & 8. Operation and Maintenance: After new system is used for a period of time, it may be out-of-date,
i.e. no longer meets its objectives. Audits are performed to assess the system’s capabilities and to
determine if it is being used correctly.
Systems need several types of maintenance:
− Debugging: A process that continues throughout the life of the system.
− Updating: Updating the system to accommodate changes in business conditions.
14 − Maintenance: That adds new functionally to the system –adding new features to the
existing system without disturbing its operation.
Maintenance is extremely high cost, often aggregating to amounts exceeding original costs
Needs to be properly planned, documented and tested, otherwise disastrous operational
problems can occur