A computer network is a collection of interconnected devices such as computers, printers, and other peripherals. These devices are linked together using cables, enabling the sharing of data and resources. Information is transmitted over these cables, allowing users on the network to exchange documents, share hardware and software, and print to the same printers. Each device connected to the network, whether it’s a computer, printer, or peripheral, is referred to as a node. Networks can range in size from small networks with a few nodes to large-scale networks with tens, thousands, or even millions of nodes.
Cabling:
The most commonly used types of network cabling are twisted-pair (10BaseT) and thin coax (10Base2). Twisted-pair cabling resembles telephone wire but contains eight wires instead of four. Thin coax is similar to the coaxial cabling used for connecting VCRs to TV sets.
Network Adapter:
A network interface card (NIC), also known as a network adapter or “NIC,” connects a computer to the network cabling. Some NICs are installed internally by opening the computer and plugging the card into an expansion slot. Older computers with 16-bit slots require a 16-bit NIC, while faster computers with 32-bit or PCI slots need a 32-bit NIC for optimal networking speeds. For Fast Ethernet networks, a network adapter supporting 100Mbps data speeds is necessary.
Hubs:
A hub is a device used to connect groups of PCs together using 10BaseT cabling. Small networks can use a hub, a few 10BaseT cables, and network adapters. Larger networks often utilize a thin coax “backbone” to connect multiple 10BaseT hubs. Each hub can connect several computers using 10BaseT cabling, allowing the creation of networks with varying numbers of nodes. Hubs are available in standard (10Mbps) and Fast Ethernet (100Mbps) versions.
LANs (Local Area Networks):
A network is a collection of independent computers that communicate with each other over a shared network medium. LANs are usually confined to a specific area, such as a building or a college campus. While LANs can be small, linking only a few computers, they can also connect hundreds of computers used by thousands of people. LANs have become prevalent in business and educational organizations worldwide due to standard networking protocols and media.
WANs (Wide Area Networks):
Networks can span multiple physical locations, which is achieved through wide area networking. WANs combine multiple LANs that are geographically separated by connecting them using dedicated leased phone lines, dial-up phone lines, satellite links, or data packet carrier services. WANs can range from a simple setup with a modem and remote access server to complex networks linking hundreds of branch offices globally using specialized routing protocols and filters to minimize data transfer expenses over long distances.
Internet:
The Internet is a global system of interconnected networks that enables various data communication services, including remote login, file transfer, email, the World Wide Web, and newsgroups. It has evolved from its initial use in military and academic institutions to become a vast conduit for information and commerce accessible to millions of users worldwide.
Intranet:
Intranets are private networks that utilize Internet-like tools but are limited to a specific organization. They provide employees with easy access to corporate information and resources through a browser-based interface.
Ethernet:
Ethernet is the most popular LAN technology used today. It offers a balance between speed, cost, and ease of installation. Ethernet supports multiple network protocols and is widely accepted in the computer marketplace. The IEEE 802.3 standard defines Ethernet’s configuration rules and how its components interact.
Protocols:
Network protocols are standards that govern computer.