Question

(b) Computers follow the same basic logical structure and perform five basic operations for converting raw input data into information. As an IT professional, technically explain in detail how processing is done from the input device such as keyboard through the activities of the central processing unit and memory. Illustrate these processes and explain how the data outputs onto your output devices such as the screen. UN (10) (a) Discuss the concept of Cache Memory and Virtual Memory as applied to storage in a computer system. UN (5) 2 (c) As part of a survey in your company to improve on performance by enhancing the use of technology in your company, you have been assigned as the head of IT to identify possible challenges and make suggestions and recommendations. Briefly present your response to management and explain your reasons. AP (10)

Answer 1

Ans b) Basic Operations of a Computer:

Computer is an electronic device which is used to perform computations(Processing) by receiving input from keyboard(or from any other input devices) and produce useful form of output on the monitor. Computer is taking input as a program written in a programming langauge and executes the program.

A basic Computer has the following Functiona Components:

1. Input

2. Processor or CPU

3.Memory

4. Output

5. Interconnection Structures(Bus system)

Input: It is used to eneter data into the computer from external world. Example: Keyboard, Mouse, Joystick etc

CPU: Central Processing Unit(CPU) also called as Heart of the computer it has the following sub parts:

i)ALU: Aritthmetic and Logic Unit used to perform all the functions/ calculations on given data

ii) Register Unit: It has a set of Registers used to store data and results tempararily during execution of a program

iii) Contro Unit: It is the brain of the computer which control entire operations of the computer. Cotrol unit generates Control Signal to perform operations and Provide Sequence(order) of Instructions to br executed

Memory: It is Storage device used to store both Data and Programs(Instructions) which can be read and Write during data processing and program execution.

Output: It is used to generate or display the result of computer operations from the computer:

Example: Monitor, Printer etc

Interconnection Structure: It is the physical wires collection used to connect above four components to act as a computer system. It is also called as Bus system which can be used internally and externally to connect other computers or other devices.

Input device and Output devices are call as IO devices which have transducers to convert data from Physical form to electrical during input and Electrical energy into Physical energy during output.

Suppose if user want to perform Addition of two Numbers 100, 200

This is written in a Machine Language form or High Level langauge form( likc C language) the enter into computer using Keyboard, then this program translated into low level langauge( Binary form) using Compiler and Object code is generated then Program will run to produce results of operation.

We use ASCII keyboard so when we eneter a particular Character ( 'A') it ASCII equalent number 65 will be stored in Memory in binary language with only 0's and 1's.

Input -----> Control Unit --------> Control Signals ------>ALU------>Memory------> Output

Input instruction is Fetch from Memory then Decoded by Control Unit which Activates ALU to perform operation then Results are stored in Memory .

a) Cache Memeory and Virtual Memory

Cache Memory:

1.Cache is a small Fast memory placed in between the Main Memory and Processor to bridge the speed gap between slower main memory and Faster Processor.

2. Cache Memory is based on the principle of Locality of Reference

3. When as Instruction is refered by a processor, the probability of next instruction to be referred is within the close visinity of previously referred instructions it is called Spacial Locality of Reference

4. Certain Instructions are needed periodically after every interval of time or specific time, this is called Temporal Locality of Reference

5. Performance of Cache is Measured by Hit Ratio =Number of Hits/ Number of References

If Hit ratio is high, Cache concept is useful else it is burden

6.When an an instruction or data is needed by a processor it first check in the Cache memory if it is found , it is called as HIT else Processor refers to mainmemory to bring entire block of data/instructions which contains required data into cache by replaceing one of the exixting cache line

7. Main Memory is organized into blocks and Cache is organised inti lines where cache line size is same as block size

8. Cache has three mapping methods to decide which main memory block is to be place in a particular cache line

---> Direct Mapping, Associate Mapping and Set Associate Mapping

9.Cache also uses Replacement algorithms to decide which cache line is used to accomodate new block

10 Cache memory can have different levels ie multiple caches can be used

Virtual Memory: It is the concept similar to Cache memory but it is not Physical memory it is only loogical memory.

1. To Execute any program it must be loaded into Mainmemory

2.When a program size is greater than main memory it is not possible to execute that prgram

3 To resolve this problem, Virtual Memory concept is used where user program is divided into modules , few modules loaded into main memory remaining made available on Secondary Storage, and Virtual Memory brings required modules on to the main memory on demand bases on the compiler requirement.

4. Virtual Memory extends main memory logically extends to Secondary Memory capacity

5. It uses Look up table to manage program modules in between Main Memory and Secondary Memory.

6. It also used page replacement alogorithms to accomodate new Secondary Memory blocks into Main Memory

Both Virtual Memory and Cache memories enhance the performance of a computer

c) As a IT Manager I Proposed the following Suggestions:

1. Educate all the staff with the usage of Computers and Smart Phones Applications

2. Reduce Mannual documentation by computerization of documents

3.Try to use customised business tools for effective resouce Management

4.Conduct Training programs on updated Technologies to staff

5. Use Positive Motivation approaches to increase productivity of staff

6.Provide Health Cards and other basic incentives to staff for secure life so we can get better performance and retain of staff

7.Use Performace appraisals to promotions

8. To be follow the organization rules and encourage new infrastructure facilities

9. Better MOUs with Relevant network and Cloud sharing companies for data security

10 Look for diverge fields of market with new technology