3e - Network Components

3e - Network Components

1. Hub

   • This connects multiple computers together in a network and allows them to share data packets
   • A hub will not examine the data packets. Instead it will be set to every port

2. Switch

   • A switch directly connects two computers or devices together so a data packet is sent directly to the port

3. Router

   • A router forwards data packets to their destination using the most efficient route
   • Uses a routing table to see how busy each path is at that moment
     • The routing table consists of all the networks it is connected to

4. Network Interface Card

   • This enables a compuer to be connected to a netowrk using a cable.
   • It allows data packets to travel back and forth between computer and network
   • Each interface card has a Media Access Control Address that is unique to that card
     • The data packet will have a destination address. If this matches the MAC address, then the NIC will allow the data packet through

5. Repeater

   • A repeater will boost the signal to its correct level
   • A signal will fade as it travels from one place to another
     • Copper cable - 100m
     • Thick Ethernet - 500m
     • Thin Ethernet - 185m

6. Bridge

   • A bridge will join two networks together, so as far as data packets are concerned, it looks like one large network
   • It is not as capable as a router, but it is less expensive

7. Wireless Access Point

   • This is a hub that communicates wirelessly instead of having physical connections through ports
   • Radio signals are sent from the device, and is received by the WAP and is then sent to the network or another WAP
   • The WAP is usually connected to a network infrastructure through a single cable connected to a switch

8. Gateway

   • This is the exit from one network and an entrance to another network.
   • It creates a bridge between two networks
   • It isn't a physical component - it is an application configured to work on an existing device, such as a router, switch or proxy server

9. Firewall

   • This is an application that is configured on a computer or network device to prevent unauthorised access to or from a network
   • It works by examining all data coming in to the network, and blocks any unacceptable traffic