1. ©G. Millbery 2001Communications and Networked SystemsSlide 1 Purpose of Network Components  Switches A device that controls routing and operation of a signal path.  Hubs A device joining communication lines at a central location, providing a common connection to all devices on the network.  Routers A communications device (can be hardware or software) which receives data and forwards it to the correct location via an appropriate route. »Can be known as a digital modem as it allows an internal network to connect to the internet. »Can connect two LANs together

2. ©G. Millbery 2001Communications and Networked SystemsSlide 2 Purpose of Network Components  Repeaters A device used to link two cable segments. With a loss of signal over distance, it amplifies the signal before passing it on. Allows you to extend the distance of a cable run and the overall length of the network.  Bridges A connection between two local area networks. Creates a logical network which can appear to users as a single network although it may physically be several different networks.

3. ©G. Millbery 2001Communications and Networked SystemsSlide 3 Purpose of Network Components (Cont.)  Modem A device or program that enables a computer to transmit data over, for example, telephone or cable lines.  Servers 1.On a local area network (LAN), a computer running administrative software that controls access to the network and its resources. 2.On the Internet or other WAN’s, a computer or program that responds to commands from a client. For example, it may contain an archive of data or program files; when a client submits a request for a file, this transfers a copy of the file to the client.

4. ©G. Millbery 2001Communications and Networked SystemsSlide 4  Select and justify an appropriate network system for a particular application, including the bandwidth required to transmit different forms of data such as text, sound, real-time sampled data and video, hardware such as file servers, hubs, repeaters and switchesbandwidth

5. ©G. Millbery 2001Communications and Networked SystemsSlide 5  Think of some information you would like to send, work out the bandwidth then work out which is the best method to use to send this.