Frequently Asked Questions
Some Basic Questions and Answers
Which Technologies of this age had led to the emergence of computer network?
The technologies are Computer technology and Communication technology with the support of VLSI Technology.
What are the two broad classifications under which Networks can be divided?
All computer networks fit in one of the two dimensions namely,
a). Transmission Technology, this focuses on the basic underlying physical network, for e.g. whether the nodes share a communication media or each pair of node has a separate
b). Scale, it focuses on the scale of network how large is your network
Mention different categories of computer networks (on the basis of scale) and distinguish one from the other.
Local Area Network (LAN): It is privately owned communication systems that cover a small area, say a building or a complex of buildings. Length is about 10 meters to few kilometers and operates at a high speed like 10 MBPS to 1000 MBPS. It has very
low error rate (1:1011).
Metropolitan Area Network (MAN): It is public or privately owned communication system that typically covers a complete city. Speed is about 10 MBPS and follows DQDB (Distributed Queue Double Bus) standard. Its reliability is moderate.
Wide Area Network (WAN): It covers a large geographical area and usually owned by a state. Data transfer rate is low (few KBPS to 10 MBPS) and error rate is much higher.
Mention important benefits of computer network.
Important benefits of computer networks are:
i) Resource sharing
ii) Powerful communication medium
iii) Higher reliability
iv) Higher flexibility
v) Lower cost
vi) Incremental expansion
How is computer networks used in marketing and sales, financial services, teleconferencing?
Computer network have led to a new age of all of these services. They have helped
in the following way to individual sector:
Marketing and sales: Computer networks are used extensively in both marketing and sales organizations. Marketing professionals use them to collect, exchange, and analyze data related to customer needs and product development cycles. Sales application includes teleshopping, which uses order-entry computers or telephones connected to order processing network, and online-reservation services for hotels, airlines and so on.
Financial services: Today’s financial services are totally depended on computer networks. Application includes credit history searches, foreign exchange and investment services, and electronic fund transfer, which allow user to transfer money without going into a bank (an automated teller machine is an example of electronic fund transfer, automatic pay-check is another).
Teleconferencing: Teleconferencing allows conference to occur without the participants being in the same place. Applications include simple text conferencing (where participants communicate through their normal keyboards and monitor) and video conferencing where participants can even see as well as talk to other fellow participants. Different types of equipments are used for video conferencing depending on what quality
of the motion you want to capture (whether you want just to see the face of other fellow participants or do you want to see the exact facial expression).
What are the two types of Transmission technologies, basis on which computer networks can be categorized?
Broadly there are two types of transmission technology:
- Broadcast networks: a single communication channel that is shared by all the machines on the network
- Point-to-point networks: This network consists of many connections between individual pairs of machines. To go from the source to destination a message (or packet)
may have to visit one or more intermediate machines
What is Internet?
Internet is a collection of networks or network of networks. Various networks such as LAN and WAN connected through suitable hardware and software to work in a seamless manner. It allows various applications such as e-mail; file transfer, remote login, World Wide Web, Multimedia, etc run across the internet.
How do you account for higher reliability and scalability of computer network?
Computer network can have a large number of computers, which can share software, database and other resources. In the event of failure of one computer, its workload can be taken over by other computers. So, it provides higher reliability than centralized computing system.
Requirement of software, hardware, database etc. increases gradually. In centralized computing system, if one computer is not able to serve the purpose, we have to replace it by new one. Replacement of new computer requires lot of investment and
effort, which can be avoided in computer network system. If there is need for more, one can buy another powerful computer, add it to computer network and use it. The various resources like computers, peripherals, etc. can be added in a scalable manner.
What are the main categories based on which applications of computer network can be categorized?
The main areas under which the applications for computer network can be categorized are as follows:
Scientific and Technical Computing
– Client Server Model, Distributed Processing
– Parallel Processing, Communication Media
– Advertisement, Telemarketing, Teleconferencing
– Worldwide Financial Services
Network for the People (this is the most widely used application nowadays)
– Telemedicine, Distance Education, Access to Remote Information, Person-toPerson Communication, Interactive Entertainment