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DTUS065 rev A.7 – June 27, 2014
V.5
Wireless security
There are many technologies available to counteract wireless network
intrusion, but currently no method is absolutely secure. The best strategy
may be to combine a number of security measures.
Possible steps towards securing a wireless network include:
1.
All wireless LAN devices need to be secured
2.
All users of the wireless network need to be trained in wireless
network security
3.
All wireless networks need to be actively monitored for weaknesses
and breaches
Available wireless security protections are:
Not broadcasting the SSID (access point only feature)
WEP encryption
WPA or WPA2 – PSK (“Pre-Shared Key”)
WPA or WPA2 – Enterprise, also known as 802.1x or RADIUS.
WEP encryption vs. WPA and WPA2 encryption
The encryption depends on the wireless topology. In ad-hoc mode, only
WEP encryption is available, because WPA requires a point-to-point link in
order to establish the cryptographic keys. In infrastructure mode, there is a
point-to-point link between each station and its associated Access Point, and
you can use WEP or WPA/WPA2.
V.5.1
WEP encryption
WEP is a method of encrypting data for wireless communication and is
intended to provide the same level of privacy as a wired network. However,
due to progress in crypto science,
WEP is not considered secure anymore
,
and cannot be used altogether with 802.11N.
To gain access to a WEP
network you must know the key. The key is a string of characters that you
create. When using WEP you will need to determine the level of encryption.
The type of encryption determines the key length. 128-bit encryption
requires a longer key than 64-bit encryption.
Keys are defined by entering a string in HEX (hexadecimal - using
characters 0-9, A-F) or ASCII (American Standard Code for Information
Interchange - alphanumeric characters) format.
ASCII format is provided so that you can enter a string that is easier to
remember. The ASCII string is converted into HEX for use over the
network. Four keys can be defined so that you can change keys easily. A
default key is selected for use on the network.
WEP authentication
Two methods of authentication can be used with WEP:
Open System
authentication
and
Shared Key authentication
.
