Stop unauthorised access of your network

Q I am worried that my neighbours might be using my wireless network to access the internet.
The activity lights on the modem router keep flashing even when my computer is turned off. What can I do to prevent this happening?

A The first step is to turn off wireless networking on the router and connect it to your computer using a network cable. There should have been one supplied in the router box and it's very rare for computers not to have a network socket on them. Connecting in this way keeps your network private until you are ready to turn wireless networking on again.

Connect to the router using a web browser following the instructions provided with it.

If you want to check if someone is on the network without permission look for the DHCP client list on the router. The router will give out network addresses to PCs automatically, saving time and hassle, and it keeps a list of the computers that have been given addresses.

This will normally be in the advanced network settings section of the router pages. If there is a computer you do not recognise, that is a sign that someone is on the network without permission, although it is possible to connect to networks without appearing in this list.

To prevent further intrusions on your network, change the SSID, the technical name for the wireless network name. Ensure it is something that you will recognise but does not contain anything that could link it to your house.

Next, enable encryption if this has not been done already. Always choose the most secure option, currently WPA, and Only use the older Wep standard if you have older devices that are not compatible with WPA.

Depending on how sophisticated you think the person accessing your network is, you may decide it is worth replacing these devices, or connecting them to the network using wires. Homeplug is a good alternative for older devices with a network socket.

Make the password for the encryption is as complicated as you can make it. This is a situation when it is perfectly acceptable to write the password down. Do not use ordinary words and mix in numbers as well. These changes should protect your network from further problems.

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