Download Management information 1

Management information 1
Prepared by John C. Mupala
ORGANISATION AND INFORMATION SYSTEMS
• An information system- a technologically implemented
medium for recording, storing, and disseminating linguistic
expressions, as well as for drawing conclusions from such
expressions.
• “information systems” means the computers, communications
facilities, computer and communications networks, and data and
information that may be recorded, processed, stored, shared, transmitted,
or retrieved by them, including programs, specifications, and procedures
for their operation, use and maintenance.
Evolution of Information Systems
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1950s and early '60s computing was based around the mainframe computer valve-based technology. Referred to as “electronic data processing systems
The invention of the transistor -the late 1960s saw the advent of the
minicomputer . In the 70’s new programming languages C and improved
operating systems with multi-tasking capabilities (UNIX) led to changes in the
role of information systems. Computers could perform more than one task at
once and for multiple users (time sharing).
This was the beginning of information systems as decision support tool and
they were called “management information systems”.
In 1980 VLSI or Very Large Scale Integration enabled millions of transistors to
fit on a chip and for the first time a whole microprocessor, the computer could
be implemented on a single chip. VLSI led to the birth of the microcomputer
and the introduction of decentralized computing.
Decentralized computing led to the fragmentation of information. This information
overload led to the introduction of “executive information systems”.
Evolution of Information Systems –
con.
• The 1980s also saw the first commercial application of artificial
intelligence techniques in the form of “expert systems”. These programs
could give advice within a very limited subject area.
• In the 1990s strategy became an important business led to the
introduction of “strategic information systems”.
• During the late 1980s and all the way through to the 1990s a new
approach to computing was developed based on placing the application at
the server and getting users to access it from a client. This development
was to create a whole new phenomenon called “The Internet”.
• The invention of hypertext and the “World Wide Web” (WWW) finally
brought the power of the internet to the masses and with it a whole
range of new applications. The systems became business models in
themselves and led to the commercialization of the Internet, and the
advent of intranets and extranets.
CHARACTERISTICS OF DATA AND
INFORMATION
• A datum is a fact that is accepted at face value. Data
is the plural for datum
• Data is unstructured, lacks context and may not be
relevant to the recipient.
• When data is correctly organized, filtered and
presented with context it can become information
because it then has "value" to the recipient.
CHARACTERISTICS OF DATA AND
INFORMATION
– In management, organizations use information in one of
the following ways:
• Planning - strategic purposes
• Control - tactical purposes
• Operating – operational purposes
– Interpreting Information
• Qualitative information: is difficult to assign a numerical value to.
• Quantitative information: on the other hand is that which can be expressed in
numerical terms.
QUALITIES OF GOOD INFORMATION
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Timeliness: Information must be delivered soon enough to be meaningful
Sufficiency:
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Completeness: is there adequate information for the purpose intended
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Level of Detail or Aggregation
– Is the information broken down into meaningful units
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Redundancy - this can be a problem if there is too much redundancy or too little redundancy
Understandable: can it be read and interpreted correctly.
Freedom from Bias: information presented with accompanying text or verbal explanation that is
likely to encourage the reader making a supporting decision
Reliability
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Decision-Relevance
Cost-efficiency - minus the cost of obtaining it
Comparability: last year vs. this year analysis is usually affected by this
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are you sure the information is correct
verifiability (can we prove it is correct or at least reproduce it)
consistency of format
Appropriateness of format
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graphical vs. tabular display
SOURCES OF DATA AND INFORMATION
• An organization is a formal group of people operating in a systematic
way to achieve one or more shared goals.
– The organisation takes inputs from suppliers, governments, industry regulators,
customers and partners, the environment, the market and other exchanges and
transforms these into outputs
– The organisation then takes in prices from competitors and perhaps pricing guidelines
from the regulator before setting its own price. Government legislation means adding
VAT to the price
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What the pricing example demonstrates is that data and information come from the environment in which an
organisation is doing business and also from within the organisation through its processes and employees. The very
process of doing business provides the sources of data and information that an organisation will typically use to create
products from raw materials.
FLOW OF DATA AND INFORMATION THROUGH THE
ORGANISATION AND OUTSIDE
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Flow of Data and Information through the organisation and outside The activities of an
organization are split into functional roles of employees and business processes which are
the routines or tasks that the employees perform.
The value chain model as described by Michael Porter
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Inbound logistics - concentrates on the supply side of the business including purchasing and storage of goods or raw
materials, production planning, quality and stock control.
Operations - those processes and activities that take place in order to convert inputs into outputs.
Outbound Logistics - all the activities required to deliver the finished goods to customers and include warehousing
techniques, stock control and transportation.
Sales and marketing - the activities that a firm engages in so that it can: inform the customers of its intent to trade
its products in the market; match the needs of the customer to the characteristics of its products or services; and
capture and fulfill demand.
Human resource management: performs the tasks of hiring and managing the human labour and developing the
firm’s intellectual capital
Technology development: includes IT infrastructure, software, research and design processes and information
management
Procurement: covers the finance and accounts department which ensures that the organization has the cash required
to run all the operations and the resources needed to continue production is concerned with inputs that are not raw
materials or directly related to the production process
COMPUTERISED INFORMATION
SYSTEMS
• A system is defined as:
– · a group of independent but interrelated elements comprising a unified whole
• These common characteristics include the following:
– Systems have a structure that is defined by its parts and processes
• Systems tend to function in the same way. This involves the inputs and
outputs of material (energy and/or matter) that is then processed causing
it to change in some way.
• The various parts of a system have functional as well as structural
relationships between each other.
• The fact that functional relationships exist between the parts suggests the
flow and transfer of some type of energy and/or matter.
• Systems often exchange energy and/or matter beyond their defined
boundary with the outside environment, and other systems, through
various input and output processes.
characteristics of a system
•characteristics of a system comprise a continuous loop of
input/process/output/feedback, all occurring within an operational
environment
ENVIRONMENTAL COMPONENTS
• The internal environmental components are those entities that can affect
the organization or be affected by the organization over which the
organization has direct control. Examples would be employees,
management, or product quality.
• The external environmental components are those entities that can affect
the organization or be affected by the organization over which the
organization does not have direct control. Examples would be customers,
government agencies, and the community at large.
– the external environment is categorized into three groups
– the direct component,
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· the indirect component
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· the nimbus component
CATEGORIES OF EXTERNAL
ENVIRONMENT
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The direct component of the external environment is defined as the entities that affect the organization or
are affected by the organization over which the organization has no direct control (definition of an
external component) but whose effect on the organization manifests itself through some kind of direct
relationship eg Customers
The indirect component of the external environment is defined as the entities that affect the organization
or are affected by the organization over which the organization does not have direct control but whose
effect on the organization manifests itself through some kind of indirect relationship (that is, they have
their effect through a direct component). E.g general community
The nimbus component of the external environment is a little more nebulous, hence the name. It is
defined as the entities over which the organization does not have direct control, but which may either
affect or be affected by the organization in special circumstances.
Boundary
• Boundary of a system we can find three kinds of
properties:
– Elements - are the kinds of parts (things or
substances) that make up a system. These parts may
be atoms or molecules, or larger bodies of matter like
sand grains, rain drops, plants, animals, etc.
– Attributes - are characteristics of the elements that
may be perceived and measured. For example:
quantity, size, color, volume, temperature, and mass.
– Relationships - are the associations that occur
between elements and attributes.
• These associations are based on cause and effect.
types of systems
• Some of the classified types include:
– Isolated System - a system that has no interactions beyond its
boundary layer. Many controlled laboratory experiments are this type
of system.
– Closed System - is a system that transfers energy, but not matter,
across its boundary to the surrounding environment. Our planet is
often viewed as a closed system.
– Open System - is a system that transfers both matter and energy and
can cross its boundary to the surrounding environment. Most
ecosystems are an example of open systems.
– Control System - a system that can be intelligently manipulated by
the action of humans.
– Ecosystem - is a system that models relationships and interactions
between the various biotic and abiotic components making up a
community or organisms and their surrounding physical environment
COMPUTERISED SYSTEMS
• A computer system - is an automated data-processing
system that uses a programmable electronic device to
store, retrieve, and process data. It is the collection of
routines, hardware, firmware and software, sufficient
to establish the processing of information and consists
of input, processing and output elements.
• A computerised information system -is a business
application of the computer. It is made up of the
database, application programs and manual and
machine procedures. It also encompasses the
computer systems that do the processing.
NETWORKS
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The purpose of business communications is to make it possible for employees, customers, suppliers and partners
to communicate whenever necessary to accomplish their goals.
• Networking
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A network is defined as a collection of hosts that are able to communicate with each other, often by relying
on the services of a number of dedicated hosts that relay data between the participants
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• Networking is implemented using:
• physical transport mediums e.g. cable or air in the case of wireless and
satellite networks;
• protocols which are the set of rules that govern how the nodes in the
network communicate with one another; and a
• Naming convention which controls how machines are identified and
grouped together
• Modern networking is dominated by three technologies:
– Ethernet (the most common physical transport);
– TCP/IP (the de-facto standard for communications protocols); and
– the domain name service (DNS) for naming and identifying hosts
PROTOCOLS AND THE OSI MODEL TCP/IP
ARCHITECTURE
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Communication is impossible without some sort of language or code. In computer
networks, these languages are collectively referred to as protocols.
Protocols - rules for the exchange of messages between two or more hosts
In order to standardise International Standards Organisation (ISO) created the Open
Systems Interconnect (OSI) model. - a 7-layer stack of protocols
1. Application layer provides a means for the user to access information on the network through an
application. Example- Telnet, File Transfer Protocol (FTP), Simple Mail Transport Protocol (SMTP) and
Hypertext Transfer Protocol (HTTP).
2. The Presentation layer transforms data to provide a standard interface for the Application layer. manipulation of the presentation is done at this layer to present the data as a service
3. The Session layer controls the dialogues (sessions) between computers. It establishes, manages and
terminates the connections between the local and remote application
4. The Transport layer provides transparent transfer of data between end users, thus relieving the upper
layers from any concern while providing reliable and cost effective data transfer. Transmission Control
Protocol (TCP), TCP, User Datagram Protocol (UDP) and Stream Control Transmission Protocol (SCTP) packets
5. The Network layer provides the functional and procedural means of transferring data sequences from a
source to a destination via one or more networks while maintaining the quality of service requested by the
Transport layer.
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The Data Link layer provides the functional and procedural means to transfer data between network entities and to detect and possibly
correct errors that may occur in the Physical layer. is split into a Media Access Control (MAC) layer and the Logical
Link Control (LLC) layer.
7. The Physical layer defines all the electrical and physical specifications for devices . cable
specifications
TCP/IP Architecture
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The OSI model is a theoretical model. It was never implemented due to inability to
agree on the standards by manufacturers
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Network layer: the lowest layer, which describes all the rules for achieving connectivity with the physical medium
over which the data will pass.
Internet Layer: defines the datagram or packet and handles the forwarding of packets from a source host to a
destination host (routing). Routers and Layer 3 switches are typical Internet layer devices
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Transport Layer: or the Host-to-Host Transport Layer. It provides end-end data delivery services.
The two most important protocols in the Transport Layer are Transmission Control Protocol (TCP)
and User Datagram Protocol (UDP).
Application Layer: sits at the top of the TCP/IP protocol architecture. This layer includes all
processes that use the Transport Layer protocols to deliver data. Applications protocols are: telnet;
ftp; SMTP; DNS; and http.
CONNECTIVITY, INTERFACES AND IP ADDRESSING
• Ethernet - a connectivity protocol In order to
connect a device or computer to a network it
needs a network interface device called a
Network Interface Card or NIC. This address is
• NIC must then be assigned an address called a
Media Access Control or MAC address. Ethernet
networks may suffer from collisions To deal with
this Ethernet is implemented as Carrier Sense
Multiple Access with Collision Detection
(CSMA/CD)
IP Addressing
• In a TCP/IP network each host is assigned an IP
address. The address used by the IPnetworking
protocol is a 32-bit number consisting of a networksegment and a host segment. IP addresses are split
up into four 8-bit numbers called octets. This format
is often referred to as the dotted quad notation. e.g
213.160.122.228
• When applying to the Network Information Centre
(NIC) for IP-addresses, you are not assigned an
address for each single host you plan to use.
Cont.
There are also two network addresses that are reserved, 0.0.0.0 and 127.0.0.0. The
first is called the default route, the latter the loopback address.
Domain Name Server System
• The Domain Name Server (DNS) system was created to translate
names into IPaddresses. DNS is a huge database listing all registered
IP addresses and their corresponding domain name.
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A local domain name server stores a table based of recent lookup
request results and also stores the IP addresses of all of the root domain
name servers.
A root domain name server stores references to master domain name
servers for a single domain (like the .com domain or the .net domain).
Multiple root domain name servers exist for each single domain, so if
one server ever crashes or is unreachable,25 the other servers that
handle the same domain will be able to handle the lookup requests.
Master domain name servers store detailed information about the hosts
in a specific domain.
Types of Networks
• Networks are distinguish by topology,
• Network topology
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In a bus topology every device has one connection on a common link, the bus. One host or
station sends a signal in both directions on the single transmission segment. All machines
receive the communication but detect whether the message is theirs and ignore it if not
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Ring topologies are those where each host is connected to the two other hosts and can
communicate in each direction. Ring topologies are more redundant than bus topologies
because if a host is down, the remaining hosts can reach one another by sending
communication in the opposite direction.
The star topology is by far the most common in use today. In this configuration, every host
is connected to a single host at the centre of the “star” or hub
a fully-meshed network topology can be implemented in which each node or host is
connected to every other node
Local, Metropolitan & Wide Area
Networks
• A local area network or LAN is a network which covers a radius of 500
metres or less. A LAN can be implemented across buildings and is
sometimes referred to as a campus area network
• A metropolitan area network is covers a geographical area of a city and
or its suburbs. It is likely to be used by an organisation that is trying to
reach as many people as possible usually for monetary reasons e.g. an
Internet Service Provider and will use existing cable infrastructure like the
Public Switched Telephone Network (PSTN) using Asymmetric Digital
Subscriber Line technology (ADSL)
• Wide area networks (WAN) cover huge distances connecting from city to
city,across regional boundaries and maybe even across the globe. The best
known WAN is the Internet.
Processing Techniques
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Batch processing is the execution of a series of ("jobs") on a computer without
human interaction. A group (or batch) of transactions are accumulated, then
processed against a master file all at one time, later in the day or a later date.
online processing such that each transaction or “job” is entered directly into
computer as and when it occurs.
Client-server computing
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Client-server is a network or distributed computing architecture which separates the client (often an application that
uses a graphical user interface) from the server.
Thin-client- Thin Client computing is when you host all of your application and data on a
central server and access it using a terminal e.g. a Windows Based Terminal (known as a Thin
Client).This is different from client - server based computing where applications and data are
stored on different computers throughout an organisation.
Types of Computer Systems
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The computer and all equipment attached to it are called hardware. The instructions that tell it what to
do are called "software." A set of instructions that perform a particular task is called a "program" or
"software program.“
The instructions in the program direct the computer to input, process and output as follows:
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Input/Output The computer can selectively retrieve data into its main memory (RAM) from any peripheral device (terminal,
disk, tape, etc.) connected to it. After processing the data internally, the computer can send a copy of the results from its
memory out to any peripheral device. The more memory it has, the more programs and data it can work with at the same time.
Storage By outputting data onto a magnetic disk or tape, the computer is able to store data permanently and retrieve it when
required. A system's size is based on how much disk storage it has. The more disks, the more data are immediately available.
Processing The computer performs all processing by "calculating," "comparing“ and "copying" the data stored in its memory
(RAM).
COMPUTER ARCHITECTURE
• It is composed of a central processing unit
(CPU), the system bus which is itself split into
a higher bandwidth front-side bus connected
to memory and on-board graphics cards for
extra speed and a PCI bus connecting
peripheral devices.
• The CPU is composed of a control unit and
arithmetic and logic unit and input/output
• registers.
How CPU function
• The function of the control unit is to fetch and
execute programming instructions. It fetches the
next instruction and loads it with associated data
into the registers and either performs move,
modify, or store actions.
• The function of the Control unit is implemented
as microcode in non-volatile Programmable Read
Only Memory (PROM). The registers that store
the instructions and data are implemented in fast
access volatile memory or RAM (random access
memory).
Cont.
• Modern computers also use pipelining. This involves loading
more than one instruction in the instruction registers and
beginning the execution process before it is required.
All modern computers implement virtual memory techniques. When a
program is being executed, only the code that is currently in focus is required
in the CPU. Thus it is possible to load the instructions from more than one
program in the CPU at the same time .
Cont.
• All of the computer logic is implemented on a
printed circuit board usually referred to as the
motherboard.
• Input Devices
– An input device is a peripheral device that
generates input for the computer such as a
keyboard, scanner or mouse.
Methods of Data input
• There are in general three classes of data input:
online; offline; and task-specific.
– Online data input: This is the most common method.
The user inputs data directly onto a backing storage
device. – Offline data input: is used when it may not necessarily
be desirable(economic), practical or possible to
capture data online.
– Application-specific input: A computer or a specialised
microprocessor can be used to read specific preformatted information.
Online data input
• Keyboards
– Positional devices: Joysticks, Gloves and Trackballs
– Pointing devices: Mouse, Stylus, Light Pen, Light
Gun, Touch screens
• Offline Input Devices are usually associated with batch
processing and include but are not limited to:
– Punched cards
– Key-storage systems
APPLICATION-SPECIFIC INPUT
DEVICES
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Application-specific Input Devices are characterised by the fact that they work only in a specific
context and can not be applied in general situations.
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Barcode readers
Laser scanners
Image scanners
Automatic number plate recognition (ANPR) systems for mass surveillance
operations, which use Optical Character Recognition (OCR) on images to
read the licence plates on vehicles
Video Image recognition systems are used by police or airport authorities to
track progress of passengers and trap criminal elements.
Magnetic Ink Character Recognition: Sometimes classed like bar codes as
optical mark recognition (OMR), MICR technology recognises the numbers or
marks on a document such as a cheque.
Point of sales systems are employed in retail situations.
Selection of input methods
• Economy: the cost of data capture
• Accuracy: the error tolerance level that is acceptable
also dictates the choice
• Time: If it takes too long to capture the data then the value
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of the results may not be useful.
Reliability: the cost of a unit being down
Flexibility: so methods are specific others are generic.
Volume: Large volumes of data may require methods that can
collect it quickly
Compatibility: the selected equipment must work with future
as well as present applications.
Output Devices
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An output device is a peripheral device that allows a computer to display or store
results of actions and/or processes (the outputs) for the computer such as a printers or
monitors.
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Human-readable output devices:
• A monitor is typically based on cathode ray tube (CRT) or liquid crystal display
(LCD)
• Printers generate their output on paper and this output is permanent.
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Ink-jet printers
Laser printers
Line printers
Plotters
• The choice of output methods depends on the following issues:
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Size of the display
The number of colours
The resolution or sharpness of the output
The volume of the output
Whether it will be permanent or transient
Costs
Connectors
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PS/2
(serial communication use an RS-232
Universal Serial Bus (USB)
Serial port
Parallel port
– parallel port uses a 25-pin connector
• Video Graphics Array: or VGA
Storage Devices
• On-board chip memory
• There are several kinds of memory chips which can be classified as
non-volatile (cannot be erased) and volatile (do not hold contents
when powered off):
– Read Only Memory (ROM) typically contains data and instructions
(programs) installed by the manufacturer typically required to start a
device. The programs may be referred to as firmware. ROM is nonvolatile
– Erasable Programmable Read Only Memory (EPROM) is a ROM that
can be erased using ultra-violet light and re-programmed.
– EEPROM are EPROM that can be erased using electronic means
allowing for selective re-programming of only the programs and data
required.
– Random Access Memory (RAM) is memory that can be used to store
data and programs only required for immediate use. RAM needs to be
continuously powered to keep the data and is thus volatile.
External Storage
• Hard disks generally accessed over one of a number
of bus types, including ATA (IDE, EIDE), SCSI, SAS,
Firewire or IEEE 1394) USB and Fibre Channel.
– Floppy disks which are read and written by a floppy disk
drive or FDD.
– Zip drives which are medium-capacity removable disk
storage system, first introduced by Iomega.
– Tape drives, also known as streamers, which are
peripheral devices that read and write data stored on a
magnetic tape. They are typically used for archival
– storage of data stored on hard drives. Tape drives are
sequential-access, and must wind past all preceding data
to read any one particular piece of data.
SOFTWARE
• System software: to integrate a computer's various capabilities,
but typically does not directly apply them in the performance of
tasks that benefit the user. Operating systems are typical of systems
software. System software acts as an interface between the
hardware of the computer and the application software that users
need to run on the computer.
• Application software: is a loosely defined subclass of computer
software that employs the capabilities of a computer directly to a
task that the user wishes to perform. The term application refers to
both the application software and its implementation. Application
software is designed to solve a particular problem or serve a
specific purpose. Examples of application software include
spreadsheets, database systems, desktop publishing systems,
program development software, and games."
Systems Software
• Systems Software including operating systems and
utilities Systems software refers to programs or
suites of programs that either operate in supervisor
mode or control a function of group of functions that
have a direct access to the low-level hardware such
as the computer itself or computer peripherals.
• Operating Systems - to as the kernel which performs
activities on behalf of the operators and user (in the case of
a mainframe) or user for a PC.