Computer Networks

10.1 INTRODUCTION TO COMPUTER NETWORKS

In the modern digital era, we live in a highly connected world where information is continuously produced, exchanged, and traced globally in real time. This extensive interconnection is possible because almost every individual and device in the digital world is linked through various means. A network, in general, is defined as a group of two or more similar things or people interconnected with each other. In everyday life, examples of networks include social networks, mobile networks, computer networks, and networks of airlines, railways, banks, and hospitals. A computer network specifically refers to an interconnection among two or more computers or computing devices. This interconnection enables the sharing of data and resources among the connected devices. The size of a computer network can vary from a small network connecting a few computers in a single room to large networks spanning multiple locations. The devices connected in a network are called nodes or hosts, which may include servers, desktops, laptops, smartphones, and other computing devices. Networks also include networking devices such as switches, routers, and modems that facilitate the connection and communication between multiple computers. Data communication in networks happens through the transmission of data divided into smaller chunks called packets. These packets travel over the network media, which can be wired (cables) or wireless (air). Each device in a network capable of sending, receiving, creating, or storing data is called a node. Nodes can be computers, printers, modems, switches, or routers. The interconnectivity provided by computer networks allows simultaneous information exchange with multiple parties using emails, websites, audio/video calls, and more. Networks also enable resource sharing, such as sharing a printer or accessing networked storage devices. Personal devices can also be connected through hotspots to form small personal networks.

• A network is a group of two or more interconnected similar things or people.
• A computer network connects two or more computing devices to share data and resources.
• Nodes in a network include computers, servers, printers, and networking devices.
• Data is transmitted in networks as packets over wired or wireless media.
• Networks enable simultaneous communication and resource sharing.
• Personal networks can be formed using hotspots connecting multiple devices.
• 📌 Network: A group of interconnected similar things or people.
• 📌 Computer Network: Interconnection of two or more computing devices for data sharing.
• 📌 Node: Any device in a network that can send, receive, or store data.

10.2 EVOLUTION OF NETWORKING

The evolution of computer networking began in the 1960s with a research project initiated by the Advanced Research Projects Agency Network (ARPANET) under the U.S. Department of Defence. The primary goal was to connect academic and research institutions located at different places to facilitate scientific collaboration. The first message was successfully communicated between the University of California, Los Angeles (UCLA) and the Stanford Research Institute (SRI). Gradually, more organizations joined ARPANET, and many independent smaller networks were formed. This marked the beginning of the expansive growth of computer networks. Over the years, technological advancements and increased demand for connectivity led to the development of various types of networks and networking devices. The timeline of networking evolution includes key milestones such as the introduction of Ethernet for local area networking, development of protocols like TCP/IP that standardized communication, and the emergence of the Internet as a global network connecting millions of computers worldwide. This evolution has transformed communication, information sharing, and resource accessibility across the globe.

• Networking evolution started in the 1960s with ARPANET.
• First message sent between UCLA and Stanford Research Institute.
• Growth from small networks to interconnected global networks.
• Development of Ethernet and TCP/IP protocols.
• Emergence of the Internet as the largest global network.
• Networking evolution enabled scientific collaboration and information sharing.
• 📌 ARPANET: The first operational packet switching network and the precursor to the Internet.
• 📌 TCP/IP: Transmission Control Protocol/Internet Protocol, fundamental communication protocols for the Internet.
• 📌 Ethernet: A set of rules for wired local area networking.