Long Answer Type Questions
1. What is MODEM ? Also Explain its type and speed.
2. Explain the tasks performed by network and Internet.
3. What are the main services provided by Internet? Explain briefly
Answers
1)Modem - A modem (portmanteau of modulator-demodulator) is a hardware device that converts data into a format suitable for a transmission medium so that it can be transmitted from computer to computer (historically over telephone wires). A modem modulates one or more carrier wave signals to encode digital information for transmission and demodulates signals to decode the transmitted information. The goal is to produce a signal that can be transmitted easily and decoded to reproduce the original digital data. Modems can be used with almost any means of transmitting analog signals from light-emitting diodes to radio. A common type of modem is one that turns the digital data of a computer into modulated electrical signal for transmission over telephone lines and demodulated by another modem at the receiver side to recover the digital data.
There are two different types of modem: Ethernet modems that plug into the network card in the computer, and wireless modems that connect to a computer using a wireless LAN (WLAN). Some modems offer dual Ethernet and USB connection. There are also routers with integrated ADSL modem.
Modem speed is a critical factor in the quality of a user's Internet experience. Technically, it is a measure of how much data can be transferred in a given amount of time. Faster modem speeds not only allow more data transfer, but they also spur on the development of richer Web content. Modem speeds influence the kinds of activities and tasks people engage in on the Internet. Improvement in this area has led to some major technological changes and helped people to connect with others from around the world like never before
2) Network - A network, in computing, is a group of two or more devices that can communicate. In practice, a network is comprised of a number of different computer systems connected by physical and/or wireless connections. The scale can range from a single PC sharing out basic peripherals to massive data centers located around the World, to the Internet itself. Regardless of scope, all networks allow computers and/or individuals to share information and resources.
Internet - The Internet (portmanteau of interconnected network) is the global system of interconnected computer networks that use the Internet protocol suite (TCP/IP) to link devices worldwide. It is a network of networks that consists of private, public, academic, business, and government networks of local to global scope, linked by a broad array of electronic, wireless, and optical networking technologies. The Internet carries a vast range of information resources and services, such as the inter-linked hypertext documents and applications of the World Wide Web (WWW), electronic mail, telephony, and file sharing.
3) In this modern world, the Internet has become essential to living, working and easily communicating with people, whether in the next room or on the other side of the world. Some important services provided by the Internet have become commonplace, like email, the World Wide Web and easy, instant access to all types of information. These now common services allow people to become a part of the much bigger world. Communication, education, e-commerce and unlimited access to information found on the Internet provide innumerable benefits.
Answer:
Modern stands for modulator- demodulator we know that computer only understands the language of 1 and 0 i.e. binary language. The modem from the sender's side ( terminal / web server) modulates the digital data into a single which is compatible with the telephone line, i.e. analog signals . the receiving modem at the workplace demodulates this analog signal back into digital data .hence, a modem modulates as well as demodulates signal .there are two types of modem : internal modem and external modem .