Typical wireless network set-up

A typical Wireless Network consists of Access Points (AP1) and Mobile Devices(MD2). There are generally 2 types of wireless networks: (a) Wireless network that includes Access Points and Mobile Devices. This wireless network set-up is commonly found in most homes and offices. Most free wireless services like Wireless@SG are also set up in this manner. (For information on how to get connected to Wireless@SG, click here); or (b) Direct connections between 2 or more Mobile Devices in the absence of an Access Point. This sort of wireless network is also known as an ad-hoc wireless network and is usually set up for a short period of time.

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Major Wireless (Wi-Fi) network security issues

A wireless network is not confined within physical boundaries. Spillage occurs when information from your wireless network goes beyond its intended coverage. Due to spillage, the following security issues can occur if you not secure your wireless network:

Unauthorised Access: Known as “piggy-backing” or “mooching”, a weakly protected wireless network can be used for unauthorised or even illegal purposes. Hackers or users with malicious intent may use your wireless network to steal your information or attack other computers on the Internet.

Sniffing/Eavesdropping: As information between the wireless network and your mobile devices is sent through the air, anyone can potentially read or capture important information such as usernames and passwords if this information is not protected.

Rogue Access Point: A rogue access point is an unauthorised access point that could be set up by someone with malicious intent. Information such as usernames and passwords can be stolen when users unknowingly connect to the Internet via the rogue access point.

War-driving: War-driving is an activity where hackers drive around the neighbourhood to record the availability of insecure wireless networks. This is usually done so that other hackers can use the insecure wireless networks for malicious purposes.

These security issues can be avoided by securing your wireless network and protecting your mobile devices as you surf.

Protect Yourself As You Surf

The following security measures are recommended to protect your mobile devices such as laptops, PDAs and handphones:

Securing Your Wireless Network

The access point (AP) is the entrance to your wireless network and it is a good practice to lock the “door” to your network by securing your AP. The procedures for securing your AP can be found in the manual that comes with your AP. The following security controls are recommended to minimise unauthorised access to your wireless network :

Steps to check which wireless network you are connected to

Make sure that you only connect authorised wireless networks. Use the following steps to check which wireless network you have connected to. If you have connected to a wireless network with authorisation, disconnect immediately and reconnect to the correct network.

1)	If the wireless network icon is visible in your system tray in the task bar, hold your mouse over the icon and the name of the wireless network to which you are connected will be pop up in a balloon.
2)	An alternative method is to double-click on the icon named 'Wireless Network Connections' in the ‘Network Connections’ menu to check the identity of the wireless network that you are currently using.

Steps to disable the auto-connect feature in your wireless settings

Disable the auto-connect feature in your wireless settings so that you will always know which wireless network you are connected to. This allows you to control which wireless network you are using and protects you from sending information through rouge APs. The steps to disable the auto-connect feature are as follows:

1)	Double click on ‘Network Connections’ icon in the Control Panel, right-click on your wireless connection and select Properties. Click on the Wireless Networks tab.
2)	Click on the ‘Advanced’ button to open the Advanced properties menu.
3)	Select the ‘Access point (infrastructure) networks only’ and uncheck ‘Automatically connect to non-preferred networks before closing the menu.

Steps to connect to your secure wireless network

To connect to your newly secured wireless network, you will have to spend some time setting up your mobile device. This initial set-up will allow your mobile devices to detect and connect to your secure wireless network in the future.

1)	In order to connect to a wireless network that does not broadcast its name, you will have to find out the settings for the wireless network from the person who secured your wireless network. You would need information such as the name of the wireless network, mode of authentication, type of encryption and the encryption key used.
2)	Double click on ‘Network Connections’ icon in the Control Panel, right-click on your wireless connection and select Properties. Click on the Wireless Networks tab.
3)	In the Preferred networks window, click the “Add” button to add your own wireless network. Enter the SSID (network name) of your wireless network.
4)	Under Network Authentication, select the appropriate authentication and encryption that is used by the wireless network AP. If you don’t select the correct authentication mode, you will not be allowed to select the correct encryption mode. If you leave network authentication set to Open, the options available for Data encryption are WEP or Disabled.
5)	Under Data Encryption, select the type of encryption that is used by the wireless network AP.
6)	Enter the encryption key which the network is using into the boxes next to ‘Network Key’ ‘Confirm network key’. Then Click on OK.
7)	Windows XP will show its progress as it connects to your network. If the Wireless Network Connection window continues to show Acquiring Network Address, you may have entered the network (encryption) key wrongly.

Glossary
(Source: Webopedia http://www.webopedia.com)