Information Technology & Systems (MB231): April 2006

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Question Paper

Information Technology & Systems (MB231): April 2006

Section A : Basic Concepts (30 Marks)
• This section consists of questions with serial number 1 - 30.
• Answer all questions.
• Each question carries one mark.
• Maximum time for answering Section A is 30 Minutes.
1. The subnet in Wide Area Network consists of
I. Transmission lines.
II. Routers.
III. Bridges.
(a) Only (I) above (b) Only (II) above
(c) Only (III) above (d) Both (I) and (II) above
(e) All (I), (II) and (III) above.
< Answer >
2. The technology present in Metro Politan Network is
I. Distributed Queue Dual Bus.
II. Fiber Distributed Data Interface.
III. Fiber Distributed Data Bus.
(a) Only (I) above (b) Only (II) above
(c) Only (III) above (d) Both (I) and (II) above
(e) All (I), (II) and (III) above.
< Answer >
3. ADP inc. a reputed BPO company, is maintaining the database of the customers office & home phone
numbers. But it is having a problem in wasting space when the customers are using only either of them.
So which of the following processes can help the company in eliminating the redundant data?
(a) Structuring (b) Randomizing (c) Analyzing
(d) Normalizing (e) Actualizing.
< Answer >
4. The difference(s) between PBX (Private Branch Exchange) and Centrex networks is/are
I. In a Centrex network the switching equipment is located in one of the telephone company’s “central
exchanges” instead of on the premises of a business.
II. Unlike PBX, a Centrex network incorporates data-over-voice technology for transmissions.
III. A Centrex network consists of large-scale networking systems that enable a business with several
offices in the same area whereas a PBX is a telephone multiplexer connecting a large number of inhouse
telephones to a smaller number of external lines that lead to the service provider’s telephone
exchange.
(a) Only (I) above (b) Only (II) above
(c) Both (I) and (II) above (d) Both (I) and (III) above
(e) All (I), (II) and (III) above.
< Answer >
5. Which of the following information systems gives top management immediate and easy access to
selective information related to the firm’s critical success factors?
(a) Transaction Processing System (b) Management Information System
(c) Decision Support System (d) Executive Information System
(e) Artificial Intelligence System.
< Answer >
6. In which of the following operations, OLAP (Online Analytical Processing) moves in the reverse
direction and automatically displays detailed data that comprise consolidated information?
(a) Consolidation (b) Drill down
(c) Slicing and dicing (d) Abstraction
(e) Encapsulation.
< Answer >
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7. In which of the following analyses, an end user makes changes to variables or relationships among them,
and observes the resulting changes in the values of other variables?
(a) What-if Analysis (b) Sensitivity Analysis
(c) Goal-seeking Analysis (d) Optimization Analysis
(e) Cost-benefit Analysis.
< Answer >
8. Which of the following is false with respect to strategic information systems planning?
(a) It is an important component of total organizational planning and focuses on the activities and
outputs of strategic business planning
(b) Companies that do strategic information systems planning generally have four objectives in mind.
viz., business alignment, competitive advantage, resource management and technology architecture
(c) Strategic information systems planning is technology driven, and not business driven
(d) Investments in information technology must be aligned with the top management's strategic agenda
(e) The backing of the company's information systems policy committee and user groups is necessary
for the investments in information technology.
< Answer >
9. Web browser and DBMS query languages and report generators enable managers at PC workstations to
get immediate responses or find and obtain customized reports as a result of their requests for the
information they need. Such reports are termed as
(a) Demand reports and responses (b) Exception reports
(c) Periodic scheduled reports (d) Push reports (e) Edit reports.
< Answer >
10. In a Database Management System, the physical level is
(a) The highest level of abstraction that describes how the data is actually stored
(b) Used to describe the customer data as a block of consecutive storage locations
(c) Used to describe each record by a type definition and the interrelationship among the records
(d) Users can see a set of application programs that hide details of the data types
(e) The highest level of abstraction that describes only a small part of the entire database.
< Answer >
11. Entity-Relationship Model falls under which of the following Data Models?
(a) Relational Model (b) Network Model
(c) Hierarchical Model (d) Object-Based Logical Model
(e) Physical Model.
< Answer >
12. In computer networks, the two local area networks can be joined by using
(a) Routers (b) Backbones (c) Bridges (d) Gateways (e) Switches.
< Answer >
13. ATM breaks voice, video and data into fixed cells of 53 bytes. What is the size of data, control
information in each cell?
(a) 48 bytes, 5 bytes (b) 49 bytes, 4 bytes
(c) 50 bytes, 3 bytes (d) 47 bytes, 6 bytes
(e) 46 bytes, 7 bytes.
< Answer >
14. In protocol hierarchy, IDU (interface data unit) is a combination of
(a) Interface control information, service data unit
(b) Interface control information, protocol data unit
(c) Protocol data unit, service access unit
(d) Interface control information, service access unit
(e) Protocol data unit, service data unit.
< Answer >
15. In OSI reference model, which of the following layers provides network transparency to the end users?
(a) Network layer (b) Physical layer (c) Presentation layer
(d) Application layer (e) Transport layer.
< Answer >
16. Which of the following is false about network architecture?
I. Data is directly transferred from layer n on one computer to layer n on another computer.
II. At source machine each layer passes data and control information to the layer below it.
III. At destination machine each layer passes data and control information to the layer above it.
(a) Only (I) above (b) Only (II) above
(c) Both (II) and (III) above (d) Both (I) and (III) above
(e) All (I),(II) and (III) above.
< Answer >
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17. In computer networks, if the data travels in either of the direction but not simultaneously, then such type
of communication is called
(a) Simplex communication (b) Half-duplex communication
(c) Full-duplex communication (d) Half-simplex communication
(e) Automatic communication.
< Answer >
18. In telecommunication networks, which of the following is/are true about telecommunication media?
I. Twisted pair cables are twisted together to reduce the noise.
II. The insulation in the coaxial cable minimizes the interference from other signals.
III. The disadvantage of fiber optic cable is slicing of the cable to make the connections.
(a) Only (I) above (b) Only (II) above
(c) Both (I) and (II) above (d) Both (II) and (III) above
(e) All (I), (II) and (III) above.
< Answer >
19. The model in which the data is stored in the series of tables is called
(a) Network Database Model (b) Object Oriented Database Model
(c) Object Relational Database Model (d) Relational Database Model
(e) Hierarchical Database Model.
< Answer >
20. Which of the following collaborative work management tools helps in generating Gantt charts?
(a) Task and project management (b) Workflow system
(c) Calendaring and scheduling tools (d) Knowledge management
(e) System flow analysis.
< Answer >
21. Mr.Suresh, an UNIX programmer, has been asked by his two colleagues, to copy some files in their
directories. But he has copied them wrongly. So which command in UNIX might be helpful for Suresh in
copying the files in respective directories without making a mistake?
(a) tar (b) cat (c) pwd (d) rm (e) cd.
< Answer >
22. In UNIX, bootstrap is
(a) The software essential for starting the system
(b) The command used for starting the system
(c) The command used for allocating memory to different tasks
(d) A system file used to store the current users
(e) A system file used to store the current directories.
< Answer >
23. Which of the following statements is/are false about return statement?
I. To return the control back to calling function we must use the key word return.
II. Every called function must contain a return statement.
III. Each return statement in a function may return a different value.
(a) Only (I) above (b) Only (II) above
(c) Both (I) and (II) above (d) Both (I) and (III) above
(e) All (I), (II) and (III) above.
< Answer >
24. Mr. Suresh, has wrote the following statement in C program.
a = 2>3? 5>4? 100:200:4>3?300:400
What will be the value of a after executing the above statement?
(a) 100 (b) 200 (c) 300 (d) 400 (e) 500.
< Answer >
25. In C language, which of the following variables default initial value is garbage value?
I. Automatic variable.
II. Static variable.
III. Register variable.
(a) Only (I) above (b) Only (II) above
(c) Both (I) and (II) above (d) Both (I) and (III) above
(e) All (I), (II) and (III) above.
< Answer >
26. In C program, if a is integer variable then the expression a = (30 x 1000) +2768 evaluates to
(a) 32768 (b) –32768 (c) 113040 (d) 0 (e) –32767.
< Answer >
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27. In C program, which of the following functions gives the current position in the file?
(a) ftell( ) (b) fpoint( ) (c) fcurrent( ) (d) fseek( ) (e) fset( ).
< Answer >
28. In C language, which of the following symbols are used for comment lines?
(a) *,* (b) / , / (c) &,& (d) /*, */ (e) */, /*
< Answer >
29. Which of the following is/are true about circular linked list?
I. Circular linked list is terminated with null terminating pointer.
II. Circular linked list is that the whole list can be processed beginning at any point.
III. Circular doubly linked lists provide the benefit of both singly liked list and circular linked list.
(a) Only (I) above (b) Both (I) and (III) above
(c) Both (I) and (II) above (d) Both (II) and (III) above
(e) All (I), (II) and (III) above.
< Answer >
30. The most important feature that Netware 4.1operating system provides is
(a) Netware directory services (b) Netware domain services
(c) Netware interface services (d) Netware administrative services
(e) Netware business services.
< Answer >
END OF SECTION A
Section B : Caselets (50 Marks)
• This section consists of questions with serial number 1 – 6.
• Answer all questions.
• Marks are indicated against each question.
• Detailed explanations should form part of your answer.
• Do not spend more than 110 - 120 minutes on Section B.
Caselet 1
Read the caselet carefully and answer the following questions:
1. Which network topology best suits Vision Brokerage Services?
(8 marks) < Answer >
2. Which communication channel best suits Vision Brokerage Services?
(5 marks) < Answer >
Vision Brokerage Services (VBS) is the market leader in financial services. It has been in the industry for more than 15
years. There is need for computerization of all earlier manual and semi manual systems. An administrator controls a
central server. All the client based stand-alone systems are located in the same office and they interact with the central
server. There is a need for interaction between the clients, but not necessarily through the server.
The development of network technologies has prompted people to consider alternatives that reduce costs and
complexity and improve reliability. Early networks used simple twisted shielded-pair (TSP) implementations. Later, the
industry adopted multi-drop buses such as Ethernet. Now we see true web-based networks (example, the World Wide
Web) implemented on the factory floor. VBS is unaware of such developments.
Caselet 2
Read the caselet carefully and answer the following questions:
3. What are the problems that might have been faced by DMA bank using file based approach? Explain.
(15 marks) < Answer >
4. What type of approach they must follow in order to come out of this problem?
(8 marks) < Answer >
DMA banking and financial services is a conglomerate of financial services and is the leader in the industry. It generates
lot of data from its transactions like debit or credit of an account, creating a new account, balance of an account,
generating monthly statements. Data is the raw material from which information is obtained. The processing of data
consists of manipulating it into a form which provides information in a format that is meaningful and usable to the
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manager or other end-user.
Initially the information needs of DMA were met using a 'manual system'. This system was very labor intensive. With
the arrival of computers, the manual filing system was moved onto a computer. This early use of computers for
gathering information was implemented through the ‘file based approach’. But, the file-based approach has created a lot
of problems whenever a particular record or a file has retrieved; the case is same even for a group of records, as all of
them are maintained in the same manner.
Caselet 3
Read the caselet carefully and answer the following:
5. How do managers use a decision support system? How is it different from an MIS?
(6 marks) < Answer >
6. How must the knowledge, experience, and insights of a manager be coupled with the outputs from a DSS to yield
good decision-making?
(8 marks) < Answer >
CitiOne Bank is implementing a Decision Support System (DSS). With DSS as part of its Quick Response Methods
(QRM) program, CitiOne Bank looks to achieve quicker and more reliable customer response and to reduce the waiting
time for a customer. The bank also expects to maintain Hs own electronic payment systems, while achieving an
expected 30 percent growth rate each year. Additionally, CitiOne Bank is looking to cut costs by significantly reducing
its trivial operations and also making more effective use of e-banking.
"Our customers want convenient banking, fast delivery, durability, just the right amount of options and no hassles
wherever they are," said Aman Jain, Application Development Manager at CitiOne Bank. The Quick Response Method
initiative is designed to support these customer goals. CitiOne Bank is implementing a DSS to provide decision making
support to planners who work in a fastpaced environment and must react quickly to customer or schedule changes. The
system also will improve operations by providing an accurate schedule and ensuring that the delivery of payments is
coordinated with other schedules that come into play.
With Microsoft Windows clients, the DSS software graphically displays the status of each job to CitiOne Bank
personnel, supporting employees, as well as management, and other departments. Operational level employees also will
use the DSS to determine and to view special instructions, to report status exceptions, and to post completed jobs. The
software displays problem areas as they occur and notifies the responsible department.
At the heart of the DSS is Graphical Process Modeling. This component fuels CitiOne Bank's Inter Branch
Reconciliation, a database that defines all the resources and activities necessary to balance the payments between the
branches. It also communicates to support centers about the activities they are required to perform.
The software translates plans or schedules into the details necessary for execution, including online enquiries with upto-
the-minute updates of accounts and the investments etc. Because the system constantly runs and reevaluates actual
status versus new status, the software identifies variances - and their impact - as they occur. Importantly, the system tells
the end user what to do next, not what has already happened. It allows schedulers to perform their real jobs - plan for
future activities - and not have to expedite.
END OF SECTION B
Section C : Applied Theory (20 Marks)
• This section consists of questions with serial number 7 - 8.
• Answer all questions.
• Marks are indicated against each question.
• Do not spend more than 25 -30 minutes on section C.
7. “An MIS would enhance the functioning of an organization to a great extent”. Identify the role and reporting
alternatives of management information systems?
(10 marks) < Answer >
8. A manufacturing company has its manufacturing facilities in Maharashtra. It sources raw materials from a small
group of suppliers. Now it is planning to install Extranet in the company. What are the strategic competitive
benefits do you see in it?
(10 marks) < Answer >
END OF SECTION C
END OF QUESTION PAPER
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Suggested Answers
Information Technology & Systems (MB231): April 2006
Section A : Basic Concepts
1. Answer: (d)
Reason: The subnet in the wide area network consists of transmission lines and routers. Hence option
(d) is answer.
< TOP >
2. Answer: (d)
Reason: The technologies present in Metro Politan Network are Distributed Queue Dual Bus and Fiber
Distributed Data Interface. Fiber distributed data bus technology is not present in Metro Politan
Network. Hence option (d) is answer.
< TOP >
3. Answer: (d)
Reason: The process of eliminating redundant data by breaking each table into smaller tables is known
as normalizing. Hence option (d) is answer.
< TOP >
4. Answer: (d)
Reason: The difference between a PBX (Private Branch Exchange) and Centrex networks is that in a
Centrex network, the switching equipment is located in one of the telephone company’s
“central exchanges” instead of on the premises of a business. A Centrex network consists of
large-scale networking systems that enable a business with several offices in the same area
whereas a PBX is a telephone multiplexer connecting a large number of in-house telephones to
a smaller number of external lines that lead to the service provider’s telephone exchange. Like
PBX, a Centrex network incorporates data-over-voice technology for transmissions. So both
statements (I) and (III) are correct. Hence option (d) is the answer.
< TOP >
5. Answer : (d)
Reason : Executive Information System gives top management immediate and easy access to selective
information related to the firm’s critical success factors.
Option (a) is incorrect. Transaction Processing System processes data generated from the
occurrence of business transactions. So, it is not applicable here.
Option (b) is incorrect. Management Information System is defined as a computer-based
system that provides flexible and speedy access to accurate data for managerial purposes. It is
not applicable here.
Option (c) is incorrect. Decision Support System provides direct support to decision-makers,
with the use of ‘what-if’ analysis, ‘optimization models’ etc. So, it is not applicable here.
Option (e) is incorrect. Artificial Intelligence System deals in computer functions associated
with human intelligence, such as reasoning, learning and problem solving. So, it is not
applicable here.
Hence, from above discussion, we can infer that option (d) is correct.
< TOP >
6. Answer : (b)
Reason : In drill down operation, OLAP (Online Analytical Processing) moves in the reverse direction
and automatically displays detailed data that comprise consolidated information.
Option (a) is incorrect. Consolidation involves aggregation of data, like simple roll-ups or
complex groupings involving interrelated data. So, it is not applicable here.
Option (c) is incorrect. Slicing and dicing refers to the ability to look at database from different
viewpoints. So, it is not applicable here.
Option (d) is incorrect. Abstraction is the process of hiding background/implementation details
and representing only the essential features. So, it is not applicable here.
Option (e) is incorrect. Encapsulation allows one to group code and data in an object, which is
a sort of wrapper. This wrapper protects code and data from being accessed by other code. So,
it is not applicable here.
Hence, from above discussion, we can infer that option (b) is correct.
< TOP >
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7. Answer : (a)
Reason : In What-if Analysis, an end user makes changes to variables or relationships among them, and
observes the resulting changes in the values of other variables.
Option (b) is incorrect. Sensitivity Analysis is a special case of What-if Analysis. Typically, the
value of only one variable is changed, but many such iterations are carried out, and the
resulting changes are observed. So, it is not applicable here.
Option (c) is incorrect. Goal-seeking Analysis is the reverse of What-if Analysis and
Sensitivity Analysis. Instead of observing how changes in a variable affect other variables,
Goal-seeking Analysis sets a target value (the goal) for a variable and then repeatedly changes
other values until the target value is achieved. So, it is not applicable here.
Option (d) is incorrect. Optimization Analysis is a more complex extension of Goal-seeking
Analysis. It attempts to find the optimum value for one or more target variables, given certain
constraints. So, it is not applicable here.
Option (e) is incorrect. Cost-benefit Analysis is concerned with whether expected savings,
increased revenue, increased profits, reductions in required investment and other types of
benefits will exceed the costs of developing and operating a proposed system. So, it is not
applicable here. Hence, from above discussion, we can infer that option (a) is correct.
< TOP >
8. Answer : (c)
Reason : Strategic information systems planning is an important component of total organizational
planning and focuses on the activities and outputs of strategic business planning.
Strategic information systems planning is business driven and not technology driven. IT
strategies are developed based on strategic business opportunities.
Hence, from above discussion, we can infer that option (c) is false with respect to strategic
information systems planning.
Options (a), (b), (d) and (e) are all true with respect to strategic information systems planning.
Hence, from above discussion, we can infer that option (c) is correct.
< TOP >
9. Answer : (a)
Reason: In Demand reports and responses, information is available whenever a manager demands it. For
example, web browser and DBMS query languages and report generators enable managers at
PC workstations to get immediate responses, or find and obtain customized reports as a result
of their requests for the information they need.
Hence, from above discussion, we can infer that option (a) is correct.
Option (b) is incorrect because Exception reports are generated only in exceptional situations.
The information content may or may not be included in periodic reports. Such reports help the
managers to take immediate remedial measures and save costs to the organization.
Option (c) is incorrect because Periodic scheduled reports use a pre-specified format, designed
to provide managers with information on a regular basis.
Option (d) is incorrect because in Push reports, information is pushed to a manager's
workstation.
Option (e) is incorrect because Edit reports describe errors detected during processing .
Hence option (a) is the answer.
< TOP >
10. Answer : (b)
Reason: In a Database Management System at the physical level, a customer record can be described as
a block of consecutive storage locations. Hence option (b) is the answer.
< TOP >
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11. Answer : (d)
Reason : Object-Based Logical Model (OBLM) is used in describing data at the logical level and at the
view level. Under OBLM, Entity-Relationship (E-R) Model falls. E-R Model is based on a
perception of a real world that consists of a collection of basic objects called entities and of
relationships (association) among these objects.
Hence, from above discussion, we can infer that option (d) is correct.
Option (a) is incorrect. The database in a Relational Model is generally a two-dimensional
table. So, it is not applicable here.
Option (b) is incorrect. The records in Network Model are organized as collections of arbitrary
graphs. So, it is not applicable here.
Option (c) is incorrect. The records in Hierarchical Model are organized as collections of trees.
So, it is not applicable here.
Option (e) is incorrect. Physical Model is used to describe data at the lowest level. So, it is not
applicable here.
Hence option (d) is the answer.
< TOP >
12. Answer : (c)
Reason : The two local area networks can be joined by using bridges. So option (c) is the answer.
< TOP >
13. Answer : (a)
Reason : ATM breaks voice, video and data into fixed cells of 53 bytes. The size of data, control
information in each cell is 48bytes, 5 bytes .Hence option (a) is answer.
< TOP >
14. Answer : (a)
Reason : IDU (interface data unit) is a combination of interface control information, service data unit.
Hence option (a) is answer.
< TOP >
15. Answer : (d)
Reason : In OSI reference model, application layer provides network transparency to the end users.
Hence option (d) is answer.
< TOP >
16. Answer : (a)
Reason : Data is not directly transferred from layer n on one computer to layer n on another computer. It
flows from top to bottom at source machine and flows from bottom to top at destination. Hence
option (a) is answer.
< TOP >
17. Answer : (b)
Reason : In computer networks, If the data travels in either of the direction but not simultaneously, then
such type of communication is called half-duplex communication. Hence option (b) is answer.
< TOP >
18. Answer : (e)
Reason : Twisted pair cables are twisted together to reduce the noise. The insulation in the coaxial cable
minimizes the interference from other signals. The disadvantage of fiber optic cable is slicing
of the cable to make the connections. Hence option (e) is answer.
< TOP >
19. Answer : (d)
Reason : The basic structure of a relational database is series of tables, which are called relations .At the
core of relational model, is the concept of table in which data is stored. Hence option (d) is
answer.
< TOP >
20. Answer : (a)
Reason : Task and project management helps in generating Gantt charts. Hence option (a) is answer
< TOP >
21. Answer : (c)
Reason : The pwd command in UNIX is used to find the current directory that is in use. So using pwd
command he can identify the current directory and can copy the files in the respective
directories successfully. Hence option (c) is answer.
< TOP >
22. Answer : (a)
Reason : The UNIX file system consists of four blocks: boot block, super block, I-node block and data
block. The boot block contains the bootstrap, the software essential for starting the system.
Hence option (a) is answer.
< TOP >
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23. Answer : (c)
Reason : To return the control back to calling function we need not use the key word return. Each return
statement in a function may return a different value. Every function statement may or may not
have return statement. Hence option (c) is answer.
< TOP >
24. Answer : (c)
Reason : a = 2>3? 5>4? 100:200: 4>3? 300:400
We should evaluate the expression from right to left.
(4 > 3)? 300 : 400 = 300
(5 > 4)? 100 : 200 = 100
a = 2 > 3? 100 : 300
a = 300
Hence option (c) is answer.
< TOP >
25. Answer : (d)
Reason : Automatic variables, Register variables will have default initial value as garbage value. The
default initial value for static variable is zero. Hence option (d) is answer.
< TOP >
26. Answer : (b)
Reason : The range of integer constant is from –32768 to + 32767. Here the expression
a = (30x1000) + 2768 evaluates to 32768. But it will not give 32768. This value exceeding the
integer constant’s range. It will give –32768. Hence option (b) is answer.
< TOP >
27. Answer : (a)
Reason : ftell() gives the current position in the file. Hence option (a) is answer.
< TOP >
28. Answer : (d)
Reason : In C language comments lines are used for user readability. The compiler will ignore the
comment lines. Comment lines are written in-between /*, */. Hence option (d) is answer.
< TOP >
29. Answer : (d)
Reason : In circular linked list there is no NULL terminating pointer. Circular linked list is that the
whole list can be processed beginning at any point. Circular doubly linked lists provide the
benefit of both singly liked list and circular linked list. So statements (II) and (III) are true.
Hence option (d) is answer.
< TOP >
30. Answer : (a)
Reason : The most important feature that Netware4.1 provides is Netware directory services which
supports a network of servers where users can log in once and access the resources of any
server depending on their access rights. Hence option (a) is answer.
< TOP >
Section B : Caselets
1. The bus topology was the first local area network topology in use. A bus network is an arrangement in a local area
network in which each workstation is connected to a main cable or link called the bus. In this pattern network
clients are strung along a single cable. The cable must be electrically terminated at each end to function properly.
In a network, a bus is a transmission path on which signals are dropped off or picked up at every workstation
attached to the line. Only devices addressed by the signals pay attention to them; the others discard the signals.
The major advantage of a bus network is a substantial reduction in the cost of cabling. Complete loops, as in ring
networks, or separate lines, as in star network, are not necessary. A bus network is simple and reliable. If one node
fails to operate, all the rest can still communicate with each other. For a major disruption to take place, the bus
itself must be broken somewhere. Bus networks are easy to expand. Additional nodes can be added anywhere
along the bus.
There are several limitations to the bus network topology. The length of the bus is limited by cable loss. A bus
network may not work well if the nodes are located at scattered points that do not lie near a common line. Excess
network traffic, a failure, may affect many users, and problems would be difficult to troubleshoot.
< TOP >
2. Communication channels can be a physical connection between two correspondents. Wires, coaxial cables and
optical fibers are used for this purpose. But from the case it is clear that the systems are located in the same
building, thus coaxial cables will be the best choice due to the following reasons:
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A coaxial cable consists of a copper or aluminum wire wrapped with spacers to insulate and protect the cable. This
insulation minimizes interference from other signals, which distorts the signals that the cable carries. For easier
installation, a group of coaxial cables may be bundled together in a larger cable. These allow high-speed data
transmission and are used as an alternative for twisted pair wire lines in high-service metropolitan areas.
< TOP >
3. DMA is a savings-bank enterprise that keeps information about all customers and savings accounts. One way to
keep the information on a computer is to store it in operating system files. To allow users to manipulate the
information, the system has a number of application programs that manipulate the files, including
• A program to debit or credit an account
• A program to add a new account
• A program to find the balance of an account
• A program to generate monthly statements
System programmers wrote these application programs to meet the needs of the bank. New application programs
are added to the system as the need arises. For example, suppose that the savings bank decides to offer checking
accounts. As a result, the bank creates new permanent files that contain information about all the checking accounts
maintained in the bank, and it may have to write new application programs to deal with situations that do not arise
in savings accounts, such as overdrafts. Thus, as time goes by, the system acquires more files and more application
programs.
This typical file-processing system is supported by a conventional operating system. The system stores permanent
records in various files, and it needs different application programs to extract records from, and add records to, the
appropriate files.
Keeping organizational information in a file-processing system has a number of major disadvantages:
• Data redundancy and inconsistency: Since different programmers create the files and application programs
over a long period, the various files are likely to have different formats and the programs may be written in
several programming languages. Moreover, the same information may be duplicated in several places (files).
For example, the address and telephone number of a particular customer may appear in a file that consists of
savings-account records and in a file that consists of checking-account records. This redundancy leads to
higher storage and access cost. In addition, it may lead to data inconsistency; that is, the various copies of the
same data may no longer agree. For example, a changed customer address may be reflected in savings account'
records but not elsewhere in the system.
• Difficulty in accessing data: Suppose that one of the bank officers needs to find out the names of all
customers who live within a particular postal-code area. The officer asks the data-processing department to
generate such a list. Because the designers of the original system did not anticipate this request, there is no
application program on hand to meet it. There is, however, an application program to generate the list of all
customers. The bank officer has now two choices: either obtain the list of all customers and extract the needed
information manually or ask a system programmer to write the necessary application program. Both
alternatives are obviously unsatisfactory. Supp that such a program is written, and that, several days later, the
same off needs to trim that list to include only those customers who have an account balance of $10,000 or
more. As expected, a program to generate such a list does not exist. Again, the officer has the preceding two
options, neither of while satisfactory. The point here is that conventional file-processing environments do no
allow needed data to be retrieved in a convenient and efficient manner. More responsive data-retrieval systems
are required for general use.
• Data isolation: Because data is scattered in various files, and files may be in different formats, writing new
application programs to retrieve the appropriate data is difficult.
• Integrity problems:. The data values stored in the database must satisfy certain types of consistency
constraints. For example, the balance of a account may never fall below a prescribed amount (say, ,$25).
Developers enforce these constraints in the system by adding appropriate code in the various application
programs. However, when new constraints are added, it is diff to change the programs to enforce them. The
problem is compounded when constraints involve several data items from different files.
• Atomicity problems: A computer system, like any other mechanical or electrical device, is subject to failure.
In many applications, it is crucial that failure occurs, the data be restored to the consistent state that existed
prior to the failure. Consider a program to transfer $50 from account A to account If a system failure occurs
during the execution of the program, it is possible that the $50 was removed from account A but was not
credited to account resulting in an inconsistent database state. Clearly, it is essential to date consistency that
either both the credit and debit occur, or that neither occurs .That is, the funds transfer must be atomic-it must
happen in its entire not at all. It is difficult to ensure atomicity in a conventional file-processing system.
• Concurrent-access anomalies: For the sake of overall performance of the system and faster response, many
systems allow multiple users to update data simultaneously. In such an environment, interaction of concurrent
dates may result in inconsistent data. Consider bank account A, containing $500. If two customers withdraw
funds (say $50 and $100 respectively) account A at about the same time, the result of the concurrent executions
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may leave the account in an incorrect (or inconsistent) state. Suppose that the programs executing on behalf of
each withdrawal read the old balance, n that value by the amount being withdrawn, and write the result back. If
two programs run concurrently, they may both read the value $500, and back $450 and $400, respectively.
Depending on which one writes the last, the account may contain either $450 or $400, rather than the correct
value of $350. To guard against this possibility, the system must maintain some form of supervision. But
supervision is difficult to provide because data may be accessed by many different application programs that
have not been coordinated previously.
• Security problems: Not every user of the database system should be able to access all the data. For example,
in a banking system, payroll personnel need to see only that part of the database that has information about the
various bank employees. They do not need access to information about customer accounts. But, since
application programs are added to the system in an ad hoc manner, enforcing such security constraints is
difficult.
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4. Database tries to overcome the problems of a file-based approach. Database arose because the definition of data
was embedded in application programs, rather than being stored separately and independently. No control over
access and manipulation of data beyond that imposed by application programs was possible. The result was the
creation of Database Management System (DBMS).
There are three main features of a database management system that make it attractive to use in preference- to
more conventional software. These features are centralized data management, data independence, and systems
integration.
In a database system, the data is managed by the DBMS and all access to the data is through the DBMS providing
a key to effective data processing. These contrasts with conventional data processing systems where each
application program has direct access to the data it reads or manipulates. In a conventional DP system, an
organization is likely to have several files of related data processed by several different application programs. The
database management system provides the interface between the application programs and the data. When changes
are made to the data representation, the metadata maintained by the DBMS is changed but the DBMS continues to
provide data to application programs as before. The DBMS transforms data wherever necessary.
This independence between the programs and the data is called data independence, which is important because
every time some change needs to be made to the data structure, the programs that were being used before the
change would continue to work. To provide a high degree of data independence, a DBMS must include a
sophisticated metadata management system.
Object Database Management System does not have this problem, as it stores all the information inserted into it as
objects. Unfortunately, it is not possible to just stop using a database system and move to another overnight.
This is where the object relational model proves its value. It allows organizations to continue using their existing
systems, without having to make major changes, and allows them the parallel use of using 'object-oriented
systems.
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5. A decision suppor system is a system under the control of one or more decision makers that assist in the activity
of decision making by providing an organized set of tools intended to impose structure on portions of the decision
making situation and to improve the ultimate effectiveness of thedecision outcome. ADSS is expected to exetend
the decision maker’s capacity in processing the information involved in making a decision. It can solve serveral
precious time for the decision maker. On the other hand, MIS is a type of information system that supports middle
and higher levels of management by providing information that is used in making decisions.
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6. DSS effectiveness depends on the degree of fit between the decsion maker, the context of the decision and the
DSS itself. A DSS can provide the decision maker with potential alternatives that might otherwise go unnoticed or
appear too complex and difficult to pursue. The tools within the DSS can stimulate the problem solver to reach
innovative insights regarding soultions and their associated outcomes. No matter how well a DSS is designed there
exists some drawbacks that limits its ability to perform reasoning processes that require distinctly human
characteristics such ascreativity, intuition, or imagination. Such cognitive activities still belong to human
experience and do not lend themsleves well to automation or machine simulation. Thus to achieve some or all of
these potential benefits, the manager must understand not only the appropriate applicaiotn of a particular decision
support sustem but also its limits. Only then will be able to make good dicisoins using his knowledge, expereience
and insight.
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Section C: Applied Theory
7. The information reports generated by a MIS can be categorized into' four major reporting alternatives:
Periodic Scheduled Reports: This form of providing information to managers uses a pre specified format,
designed to provide managers with information on a regular basis. Examples of such periodic schedules are daily /
weekly sales analysis reports, monthly financial statements, etc.
Exception Reports: These reports are generated only in exceptional situations. The information content mayor
may not be included in periodic reports. These reports help the managers to take immediate remedial measures and
save costs to the organization.
Demand reports and responses: The information is available whenever a manager demands it. For example, web
browser and DBMS query languages and report generators enable managers at PC workstations to get immediate
responses, or find and obtain customized reports as a result of their requests for the information they need.
Push reporting: Information is pushed to a manager's workstation. Many companies are using web casting
software to selectively broadcast reports and other information to the networked PCs of managers, over their
corporate Intranet.
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8. Today when business environment is changing across the world, extranets have become an important business tool
that take advantage of Internet- technology to achieve real cost savings, faster, responses to changing business
conditions and becoming more customer centric.
For a manufacturing company, deployment of extranets provides strategic competitive benefits.
• Enabling manufacturing companies to form stronger relationships with their suppliers by allowing them to
share mission-critical information with each other.
• Automate their supply chains, improve inventory management, optimize business processes and speed their
response time to the customers.
• Manufacturers can outsource all component manufacturing through extranets.
• Engineers can discuss design changes with component manufacturers on real time basis through extranet.
They can securely access and download new designs and immediately implement changes.
• Extranets can provide instantaneous feedback on market trends.