6
Service Set Identification (SSID)
The Service Set Identification (SSID) is a thirty-two alphanumeric character (maximum) string identifying the
wireless local area network. Some vendors refer to the SSID as “network name”. In order for stations to
communicate with each other, all stations must be configured with the same SSID.
A wireless LAN consisting of nodes operating in ad-hoc configuration without an access point is called a Basic
Service Set (BSS). All nodes in a BSS must use the same Basic Service Set ID (BSSID).
In an infrastructure configuration with access points, multiple BSS can be configured to form an Extended Service
Set (ESS). In this configuration, the access points are configured with the same Extended Service Set ID (ESSID).
Wireless clients configured with the same ESSID can freely roam from one Access Point domain to another and still
maintain seamless connection to the network
Authentication and WEP Encryption
The absence of a physical connection between nodes makes the wireless links vulnerable to information theft. To
provide a certain level of security, IEEE 802.11 standard has defined two types of authentication methods, Open
System and Shared Key. Open System authentication is a null algorithm. Shared Key authentication is an algorithm
where both the transmitting node and the receiving node share an authentication key to perform a checksum on the
original message. By default, IEEE 802.11 wireless devices operate in an open system network.
Wired Equivalent Privacy (WEP) data encryption is utilized when the wireless nodes or access points are configured
to operate in Shared Key authentication mode. There are three shared key methods implemented in Netgear’s
802.11a solutions: the standard based forty-bit WEP data encryption and 128-bit WEP data encryption plus the
extended 152-bit WEP data encryption.
The forty-bit WEP data encryption method allows for a five-character (forty-bit) input. Additionally, 24 factory-set bits
are added to the forty-bit input to generate a 64-bit encryption key. (The 24 factory-set bits are not user
configurable.) This encryption key will be used to encrypt/decrypt all data transmitted via the wireless interface.
Some vendors may refer to the forty-bit WEP data encryption as 64-bit WEP data encryption since the actual
encryption key used in the encryption process is 64 bits wide.
The 128-bit WEP data encryption method consists of 104 configurable bits and the 152-bit WEP data encryption
method consists of 128 configurable bits Similar to the forty-bit WEP data encryption method, the remaining 24 bits
are factory set and not user configurable.
EncryptionKey Size
# of
Hexadecimal Digits
Example of Hexadecimal Key Content
64-bit
(24+40)
10
4C72F08AE1
128-bit
(24+104)
26
4C72F08AE19D57A3FF6B260037
152-bit
(24+1280)
32
4C72F08AE19D57A3FF6B26003715DAC2
Summary of Contents for HA501 - 802.11a Wireless 32-Bit Card Bus Adapter
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