ZyXEL NBG-419N Guia Do Utilizador

 Chapter 11 Wireless LAN

NBG-419N User’s Guide

Normally, the AP acts like a beacon and regularly broadcasts the SSID in the area. 
You can hide the SSID instead, in which case the AP does not broadcast the SSID. 
In addition, you should change the default SSID to something that is difficult to 
guess.

This type of security is fairly weak, however, because there are ways for 
unauthorized devices to get the SSID. In addition, unauthorized devices can still 
see the information that is sent in the wireless network.

Every wireless client has a unique identification number, called a MAC address.

1

 A 

MAC address is usually written using twelve hexadecimal characters

2

; for 

example, 00A0C5000002 or 00:A0:C5:00:00:02. To get the MAC address for each 
wireless client, see the appropriate User’s Guide or other documentation.

You can use the MAC address filter to tell the AP which wireless clients are allowed 
or not allowed to use the wireless network. If a wireless client is allowed to use the 
wireless network, it still has to have the correct settings (SSID, channel, and 
security). If a wireless client is not allowed to use the wireless network, it does not 
matter if it has the correct settings.

This type of security does not protect the information that is sent in the wireless 
network. Furthermore, there are ways for unauthorized devices to get the MAC 
address of an authorized wireless client. Then, they can use that MAC address to 
use the wireless network.

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.

1.

Some wireless devices, such as scanners, can detect wireless networks but cannot use wireless networks. 

These kinds of wireless devices might not have MAC addresses.

2.

Hexadecimal characters are 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, and F.