Page 1 : Chapter-I, 1. What is Computer Network?, Ans: When two or more computers are connected through a medium and exchange information, and resources between them, then it is called as a computer network., 2. What are the advantages of computer Network?, Ans: The following are the advantages of the computer network., Sharing Files, data and information: Information can be shared easily through the server., Sharing Hardware and Software: Hardware and software can be shared easily. For example a, single printer can be used in two or more computers., Communication Media: Network provides fast communication through e-mail, Voice & Video, calls., File Integrity: File integrity remains continuous due to network., Cost Effective: Network reduces the cost of system as it helps to share hardware and software., Reliability: Network is reliable as if one computer fails then data can be recovered from other, computer in the network., Flexibility: Network is flexible as devices can be added and removed from it easily., Backup: Information can be backed up to a server and can be restored from it easily., Security: Network provides security., 3. What was the first computer network?, Ans: The first network is ARPANET ( Advanced research Projects Agency Network) started in, 1969 in U.S., 4. What are the different components of a computer Network?, Ans:,
Computer: Two types of computers are used in network., o Client/Workstation/node: It is a normal computer connected to a network., o Server: It is a powerful computer, responsible for controlling other nodes and, sharing resources.,
Network Interface Card(NIC) : It is a device attached to a computer that helps to, establish connection to a network. Each NIC has unique physical address known as MAC(, Media Access Control) Address.,
HUB/Switch: It allows to connect multiple computers to a single network.,
Network operating system software: Different OS are used in Server computer such as, Windows NT, Novell Netware, Apache, Glassfish, Linux, Unix, etc.,
Transmission Media: Different Transmission media like Twisted pair cable, Co-axial, cable, Bluetooth, Wi-Fi, etc are used to carry signal from one computer to another., 5. What is data communication? What are the conditions it must fulfill?, Ans: Exchange of data between computers through communication medium is known as data, communication., The Conditions it must fulfill are:, Delivery: Data should be delivered at proper place., Accuracy: It should be free from fault., Time limit: Data should reach destination without any delay.

Page 2 : 6. What are the components of data communication?, Ans: The following are the components of data communication.,
Message: It is the information which is to be shared.,
Sender: It prepares information and sends it.,
Medium: it carries information from sender to receiver.,
Receiver: It receives information.,
Protocol: It is a set of rules under which data transmission takes place., 7. Explain different modes of data transmission., The following are the different modes of data transmission., Simplex: In simplex data flows only in one direction i.e. from sender to receiver. Reverse is not, possible. Example- Television communication., Half Duplex: In Half duplex data flows in both direction but not at a time. Example- Walky-talky, system., Full Duplex: In Full duplex data flows in both directions at a time. Example- Telephone system.