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WLAN1500 Wireless PC LAN Card
4.7 MORE ON SSID
Service Set Identification (SSID)
The Service Set Identifi cation (SSID) is a thirty-two alphanumeric character (maximum) string identifying the wireless local area network. ParkerVision-Wireless refers to the SSID as network name. For stations to communicate with each other, all stations must be confi gured with the same SSID. A wireless LAN consisting of nodes operating in Ad-Hoc confi guration 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 AP (Access Point) confi guration, multiple BSS can be confi gured to form an Extended Service Set (ESS). In this confi guration, the Access Points are confi gured with the same Extended Service Set ID (ESSID). Wireless clients confi gured with the same ESSID can freely roam from one Access Point domain to another and still maintain a seamless connection to the network.
4.8 MORE ON WEP ENCRYPTION
Authentication and WEP Encryption
Wireless links are vulnerable to information theft. To provide a certain level of security, IEEE
802.11standard has defi ned 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 confi gured to operate in Shared Key authentication mode. ParkerVision-Wireless utilizes the following 802.11b solutions: the standard based 64-bit WEP data encryption and 128-bit WEP data encryption. The 64-bit WEP data encryption method allows for a fi ve-character (40 bits) KEY. Additionally, 24 factory-set bits are added to the 40-bit input to generate a 64-bit encryption key. (The 24 factory-set bits are not user confi gurable.) This encryption key will be used to encrypt/decrypt all data transmitted via the wireless interface. The 128-bit WEP data encryption method consists of 104 confi gurable bits. Similar to the 64-bit WEP data encryption method, the remaining 24 bits are factory set and not user confi gurable.
