network hardware

network hardware

1. wires/cables

   • FIBRE OPTIC: made from glass that is very flexible when very thin. it is made from glass because light can travel down it and light is the fastest moving thing known to man. the transmitter sends light down it.
     • ADVANTAGES:the individual cables are thinner, so larger quantities of cable can be joined together compared to copper. There is less interference than copper. There is less chance for degeneration
     • DISADVANTAGES:the UK telephone network still has areas that use copper cable. Replacing copper with fibre optic cabling is expensive
   • COPPER:Copper cable uses electrical signals to pass data between networks. There are three types of copper cable: coaxial, unshielded twisted pair and shielded twisted pair. Coaxial degenerates over long distances. Unshielded twisted pair is made by twisting the copper cables around each other and this reduces degeneration. Shielded twisted pair uses copper shielding around the twisted wires to make them less susceptible to interference
     • ADVANTAGES: a cabled telephone can be powered directly from the copper cable, so the phone will still work if there is a loss of power copper can be cheaper to set up than fibre optic cabling
     • DISADVANTAGES: degenerates over long distances

2. ROUTERS: A router can form a LAN by connecting devices within a building. It also makes it possible to connect different networks together. Homes and businesses use a router to connect to the internet. A router can often incorporate a modem within the hardware.

3. MODEMS: A modem enables a computer to connect to the internet over a telephone line. A modem converts digital signals from a computer to analogue signals that are then sent down the telephone line. A modem on the other end converts the analogue signal back to a digital signal which another computer can understand.

4. HUBS: A hub broadcasts data to all devices on a network. This can use a lot of bandwidth as it results in unnecessary data being sent - not all computers might need to receive the data. A hub would be useful to link up a few games consoles for a local multiplayer game using a wired LAN.

5. BRIDGES: A bridge is used to connect two separate LAN networks. A computer can act as a bridge through the operating system. A bridge looks for the receiving device before it sends the message. This means that it will not send a message if the receiving computer is not there. It will check to see if the receiver has already had the message. This can help save unnecessary data transfers, which improves the performance of a network.

6. SWITCHES: A switch performs a similar role to a hub and a bridge but is more powerful. It stores the MAC addresses of devices on a network and filters data packets to see which devices have asked for them. This makes a switch more efficient when demand is high. If, for example, a game involved lots of data being passed between machines, then a switch could reduce the amount of latency.

7. WAP: Wireless access points (WAPs) are required to connect to a network wirelessly. WAPs are usually built into the broadband router.