Chapter 7 Wireless
EMG6726/8726-B10A User’s Guide
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7.8.3.1 SSID
Normally, the EMG acts like a beacon and regularly broadcasts the SSID in the area. You can hide the
SSID instead, in which case the EMG 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 wireless devices to
get the SSID. In addition, unauthorized wireless devices can still see the information that is sent in the
wireless network.
7.8.3.2 MAC Address Filter
Every device that can use a wireless network 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 device in the wireless network,
see the device’s User’s Guide or other documentation.
You can use the MAC address filter to tell the EMG which devices are allowed or not allowed to use the
wireless network. If a device is allowed to use the wireless network, it still has to have the correct
information (SSID, channel, and security). If a device is not allowed to use the wireless network, it does
not matter if it has the correct information.
This type of security does not protect the information that is sent in the wireless network. Furthermore,
there are ways for unauthorized wireless devices to get the MAC address of an authorized device. Then,
they can use that MAC address to use the wireless network.
7.8.3.3 User Authentication
Authentication is the process of verifying whether a wireless device is allowed to use the wireless
network. You can make every user log in to the wireless network before using it. For wireless networks,
you can store the user names and passwords for each user in a RADIUS server. This is a server used in
businesses more than in homes. If you do not have a RADIUS server, you cannot set up user names and
passwords for your users.
Unauthorized wireless devices can still see the information that is sent in the wireless network, even if they
cannot use the wireless network. Furthermore, there are ways for unauthorized wireless users to get a
valid user name and password. Then, they can use that user name and password to use the wireless
network.
7.8.3.4 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.
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.
