Unit 1: Computer Networks — Short Questions

A computer network is a group of connected computers and devices that can communicate and share data, files, and resources with each other using cables or wireless signals.

Computer networks are used for Internet browsing to access information worldwide, and by schools for online classes and learning systems. (Other valid uses include banks using networks for online transactions and ATMs, and social media platforms working through computer networks.)

Network architecture is the overall design of a computer network. It shows how computers, servers, and other devices are arranged and defines how data is transmitted across the network, including hardware, software, and communication rules.

Two components of a computer network are the Network Interface Card (NIC), which allows a device to connect to the network, and the router, which connects different networks together and directs data packets to their destination.

The OSI (Open Systems Interconnection) model is a standard model used to understand network communication. It has seven layers, each performing a different function, and it helps different systems communicate properly.

Two network topologies are Bus topology, in which all devices are connected to a single main cable, and Star topology, in which all devices connect to a central hub or switch. (Ring, Mesh, and Tree are the other topologies covered in the chapter.)

A Local Area Network (LAN) connects devices within a small area such as a home, school, or office. It provides high data transfer speed, is usually owned and managed by a single organization, and commonly uses Ethernet and Wi-Fi.

A router connects different networks together and directs data packets to their correct destination. It uses IP addresses to send data, connects local networks to the Internet, and also improves network security and control.

A network protocol is a set of rules for communication. It defines how data is formatted and transmitted and controls error handling and data delivery. All devices in a network must follow the same protocol so that data exchange is smooth; examples include TCP/IP and HTTP.

DNS (Domain Name System) converts website domain names into IP addresses, so users do not need to remember numeric addresses to access websites. DNS servers perform this translation process and it plays a key role in Internet use.