Chapter 7 Wireless LAN

7.10.3.4 Encryption

Wireless networks can use encryption to protect the information that is sent in the wireless network. Encryption is like a secret code. If you do not know the secret code, you cannot understand the message.

The types of encryption you can choose depend on the type of authentication. (See Section 7.10.3.3 on page 105 for information about this.)

Table 30 Types of Encryption for Each Type of Authentication

 

 

NO AUTHENTICATION

RADIUS SERVER

Weakest

No Security

WPA

 

 

 

 

 

 

Static WEP

 

 

 

 

 

 

 

WPA-PSK

 

Strongest

 

 

 

WPA2-PSK

WPA2

 

 

 

 

For example, if the wireless network has a RADIUS server, you can choose WPA or WPA2. If users do not log in to the wireless network, you can choose no encryption, Static WEP, WPA-PSK, or WPA2-PSK.

Usually, you should set up the strongest encryption that every device in the wireless network supports. For example, suppose you have a wireless network with the AMG1312-T Series and you do not have a RADIUS server. Therefore, there is no authentication. Suppose the wireless network has two devices. Device A only supports WEP, and device B supports WEP and WPA-PSK. Therefore, you should set up Static WEP in the wireless network.

Note: It is recommended that wireless networks use WPA-PSK, WPA, or stronger encryption. The other types of encryption are better than none at all, but it is still possible for unauthorized wireless devices to figure out the original information pretty quickly.

When you select WPA2 or WPA2-PSKin your AMG1312-T Series, you can also select an option (WPA compatible) to support WPA as well. In this case, if some of the devices support WPA and some support WPA2, you should set up WPA2-PSKor WPA2 (depending on the type of wireless network login) and select the WPA compatible option in the AMG1312-T Series.

Many types of encryption use a key to protect the information in the wireless network. The longer the key, the stronger the encryption. Every device in the wireless network must have the same key.

7.10.4 Signal Problems

Because wireless networks are radio networks, their signals are subject to limitations of distance, interference and absorption.

Problems with distance occur when the two radios are too far apart. Problems with interference occur when other radio waves interrupt the data signal. Interference may come from other radio transmissions, such as military or air traffic control communications, or from machines that are coincidental emitters such as electric motors or microwaves. Problems with absorption occur when physical objects (such as thick walls) are between the two radios, muffling the signal.

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AMG1312-T Series User’s Guide