Computer Networks Unit 1 – BTA 3O Ms. Chytra

Introduction to Networks Most people working in an office with more than a few computers will be using some form of network As networks become easier to setup and maintain more home users are also setting up networks This is done to share resource such as disk space, printers, Internet connections and access to software

What is a Network? A network is basically two or more computers connected through a cable, wire or wireless network which share resources Network software controls how the computers communicate There are dozens of different types of networks, which are impossible to cover in an introduction course This course focuses on home and small business networks

Local Area Network (LAN) A LAN connects 2 or more communicating devices within 2,000 feet, usually within the same building. Allows a large number of users to share corporate resources, allow the office to pool resources such as printers and fax machines, and eliminates some of the need for paper.

LAN Topologies LAN’s come in an assortment of topologies. A topology is the physical layout and connectivity of a network. 5 basic types of topologies include: star, bus, ring, hierarchical, and hybrid. Each topology has its own strengths and weaknesses.

Connecting to a Network To connect computers each of the computers needs a network card with a connection that allows a cable to be connected to it For a wireless connection, the computers must be within the range of a wireless router Two computers can be connected directly using a bi- directional cable but if the computers are some distance away a router is necessary The router connects all the computers in your local network together, allows more than two computers to connect, or can be used to connect two local area networks together to create a wide area network.

Network Setup Some form of network software is required The network protocol determines how computers become part of the network and how they are recognized The network must have a name and you can use some creativity at this point Each computer can also have a unique name that other computers on the network can access them with The router is usually setup to assign each computer on the network with a unique identifier called an IP address.

Networks and Sharing An advantage of networks is that the network users are able to share resources such as the printer, or file space Organizations have parts of the network that are either not accessible or accessible only through a password File and print sharing must be enabled on the computer that will be used

Types of Networks Server/client networks must have a server running before the computers can communicate Peer-to-peer networks allows any computer to communicate with another member of the network directly When a computer in the peer-to-peer network is turned on the computer recognizes the network and can access resources on the other computers Networks can also be open to remote secure access through a virtual private network VPN allows a computer to connect to a computer or network through the Internet.