BSc. Solutions and Notes: 2073-Solution of Computational Course (Computer Science) : Short Answer Question

Short Answer Question

Attempt any FIVE questions.

4) Discuss different characteristics of computer. (6)

Ans:

The different characteristics of computer are:

High speed : Computer is a very fast device. It has units of speed in microsecond, nanosecond and even the picoseconds. It can perform millions of calculation in a few seconds.
Accuracy : They are accurate. The calculations are 100% error free. It gives false result only when wrong data is entered. This is known as GIGO ( Garbage In Garbage Out).
Storage Capacity : Storage is very important characteristics of computers. It can store large amount of data. At present, hard disks are available in hundreds of Giga Bytes (GB).
Diligence : Unlike human beings, a computer is free from monotony, tiredness and lack of concentration. It can do repeated work with same speed and accuracy.
Versatility : A computer is a versatile machine capable of performing all kind of task. A computer is very flexible in performing the jobs to be done.
Automatic : As it is an automatic machine. Once data and programs is given to computer and stored in computer memory, the program and instruction can control the program execution without human interaction.
Reliability : It is a reliable machine. Computers are designed to make maintenance easy.
No IQ : A computer is a machine that has no intelligence to perform any task or we can say it cannot take decision on its own.
No feeling : It has no feeling or emotions.

5) What is operating system? Discuss different types of operating system. (2+4)

Ans:

Operating system is a system software that is responsible for controlling and coordinating computer hardware and providing easy interface to the application programmers and users by hiding underlying complexities of computer hardware. Thus, operating system acts as an interface between users or application programs and computer hardware. Some examples are Windows, Unix, Linux, Mac OS, etc.

The different types of operating system are:

Batch processing operating system - In a batch processing operating system environment, user submit jobs to a central place where these jobs are collected into a batch and subsequently placed on an input queue at the computer where they will be run.
Time sharing operating system - In this operating system, a computer provides computing services to several or many users concurrently on line.
Real time operating system - It is designed to service those applications where response time is of the essence in order to prevent error, misrepresentation or even disaster. Eg. Operating system handling airlines reservation, machine tool control and monitoring of a nuclear plant.
Multiprogramming operating system - It is a system that allows more than one active user program (or part of user program) to be stored in main memory simultaneously. A time sharing system is a multiprogramming system but a multiprogramming system is not necessarily a time sharing system.
Multiprocessing system - It is a computer hardware configuration that includes more than one independent processing unit. Eg. Computer hardware complexes found in major scientific or commercial applications.
Network operating system - It is the collection of physically interconnected computers. The operating system of each of the interconnected computers must contain provisions for handling communication and transfer of program and data among the other computers with which it is connected.
Distributed operating system - A distributed computing system consists of a number of computer that are connected and managed so they automatically share the job processing load among the constituent computers, or separate the job load as appropriate particularly configured processors.
Operating systems for embedded devices - An embedded systems (such as cellphones, washing machine, juice mixture, industrial robot control, etc.) become more complex hardware wise with every generation. So it requires specific operating system. Eg. Nexus’s Conix, Sun’s Java OS, Palm computing’s Palm OS, etc.

6) What is wireless networking? Discuss the benefits of using wireless network. (2+4)

Ans:

A wireless network is a computer network that uses wireless data connections between network nodes. Wireless networking is a method by which homes, telecommunications networks and business installations avoid the costly process of introducing cables into a building, or as a connection between various equipment locations. This implementation takes place at the physical level (layer) of the OSI model network structure.

Examples of wireless networks include cell phone networks, wireless local area networks (WLANs), wireless sensor networks, satellite communication networks, and terrestrial microwave networks.

Benefits of using wireless technology are:

1) Increased efficiency

Improved data communications lead to faster transfer of information within businesses and between partners and customers.

2) Access and availability

Because wireless technology allows the user to communicate while on the move, user is rarely out of touch. User don’t need extra cables or adaptors to access office networks.

3) Flexibility

Office-based wireless workers can network without sitting at dedicated computers and can continue to do productive work while away from the office. This can lead to new styles of working, such as home working or direct access to corporate data while on customer sites.

4) Cost savings

Wireless networks can be easier and cheaper to install, especially in listed buildings or where the landlord will not permit the installation of cables.

5) New opportunities

Wireless networking could allow you to offer new products or services.

7) Why do we need internet? What are the benefits of internet? (2+4)

Ans:

There are different services of internet such as online communication, software sharing, exchange of views on topics of common interest, posting of information of general interest, product promotion, feedback about products, customer support service, online journals and magazines, education and research, entertainment, exploring news and last technologies, software downloading, etc. so to use those services, we need internet.

The advantages of internet are:

Internet contains an endless supply of knowledge and information that allows you to learn about almost any topic or question you may have.
With the internet, we can send and e-mail to anyone in the world and often have it delivered in less than a minute. So, it helps in connection, communication and sharing.
With the help of GPS technology, the Internet can help map and direct you to almost every place in the world.
The Internet provides access to bank account to view the balance, make transactions, and send money. Also, many services enable you to view and pay bills electronically.
The Internet gives everyone access to an endless supply of entertainment, with access to watch videos, watch movies, listen to music, and even play games online

8) What is the characteristics of multimedia? Discuss. (6)

Ans:

A multimedia system is a system that is capable of processing multimedia data and applications. One of the main requirement of multimedia system is a real time operation. The different components of multimedia are text, image, audio, video and animation.

Following are the characteristics of multimedia:

Computer Controlled - Multimedia system is computer controlled. Components of computer multimedia such as audio, video, text, images and animation are computer controlled. User provide command and with the help of multimedia, computer system interprets output.
So multimedia must be computer controlled.
Integrated - Multimedia is used in many applications. Different components of multimedia integrate and operate to provide desirable procedure and outputs. For example, when we open a webpage, text, image, audio, animation and video integrates smoothly to provide better experience to user.
So multimedia system are integrated.
Digitally - Multimedia is digitally operated. The different information they handle must be digital. We cannot represent all components of multimedia without using digital platforms.
So information they handle must be digitally represented.
Interactive - The use of multimedia components without their interaction do not fulfill the objective of multimedia. It should be interactive to user and provide better experience to the user.
So interface to the final presentation of media is usually interactive.

9) What is firewall? What are the uses of firewall? (2+4)

Ans:

Firewall is a system designed to prevent unauthorized access to or from a private network. It can be implemented In both hardware and software or a combination of both.

Hardware firewalls can be purchased as a stand alone product but are also typically found in routers and should be considered as important part of system and network set-up.

Software firewalls are installed on your computer.

Following are the uses of firewall.

It blocks incoming data that might contain a hacker attack.
It hides information about the network by making it seem that all outgoing traffic originates from the firewall rather than the network. This is called Network Address Translation (TAN).
It screens outgoing traffic to limit internet use and/or access to remote sites.
It makes the system safe to use.
to protect your personal computer and private network from malicious mischief.
It can prevent outside computers to attack on computers inside the network.
Firewalls can be programmed to prevent access to certain websites (like social networking sites.
Firewalls can be configured to prevent employees from sending certain types of emails or transmitting sensitive data outside of the network.

10) Write short notes on: (3+3)

Computational nano-science

Security policy

Ans:

a) Computational nano-science : It is the field that is concerned with modeling of large scale computer stimulation in order to understand the new nanoscale phenomena and regime.

In nanotechnology, the numbers are especially important because things are to be built and require very high accuracy. Nano system presents new type of multi scale modeling and algorithmic time and storage challenges. Hardware and software tools to solve some of the nano science modeling problems already exists. Software tools and application oriented computer programming languages that already exist must be assembled and investigated for their suitability in solving nano system problems. Molecular Workbench (MW) is another tools used in computational nano science.

b) Security policy : Security policy is just a statement about what is allowed and not allowed to do in a system while security mechanism is a procedure how to implement the security policy. Policies may be presented mathematically, as a list of allowed (secure) and disallowed (non-secure) states.

Formulating security policy:

It depends upon the needs of particular organization. Main purpose of security policy is to secure organizational resources. Following steps id followed while formulating security policy.