Prevent unwanted computers from connecting to your wireless network
Topic: NETWORK TECHNOLOGY
General Network Techniques - When computers communicates on a network, they send out data packets without knowing if anyone is listening. Computers in a network all have a connection to the network and that is called to be connected to a network bus. What one computer sends out will reach all the other computers on the local network.
For the different computers to be able to distinguish between each other, every computer have an unique ID called MAC-address (Media Access Control Address). This address is not only unique on your network but unique for all devices that can be hooked up to a network. The MAC-address is tied to the hardware and have nothing to do with IP-addresses. Since all computers on the network receives everything that is sent out from all other computers the MAC-addresses is primarily used by the computers to filter out incoming network traffic that is addressed to the individual computer.
When a computer communicates with another computer on the network, it sends out both the other computers MAC-address and the MAC-address of its own. In that way the receiving computer will not only recognize that this packet is for me but also, who sent this data packet so a return response can be sent to the sender.
On an Ethernet network as described here, all computers hear all network traffic since they are connected to the same bus. This network structure is called multi-drop.
One problem with this network structure is that when you have, let say ten (10) computers on a network and they communicate frequently and due to that they sends out there data packets randomly, collisions occur when two or more computers sends data at the same time. When that happens data gets corrupted and has to be resent. On a network that is heavy loaded even the resent packets collide with other packets and have to be resent again. In reality this soon becomes a bandwidth problem. If several computers communicate with each other at high speed they may not be able to utilized more than 25% of the total network bandwidth since the rest of the bandwidth is used for resending previously corrupted packets.
The way to minimize this problem is to use network switches.
LANeye can run on any of your network connected computers and still detect all computers and other network devices that sits on the same local network.
Learn about network switches in the next section.
How computers communicate on a network.
How network switches divide networks in to zones but still let broadcast packets pass them freely.
The difference between MAC-addresses and IP-addresses and how they are used on a local network.