Wlan1500, Wireless pc lan card – ParkerVision WLAN1500 User Manual

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WLAN1500

Wireless PC LAN Card

4.7 MORE ON SSID

Service Set Identiﬁ cation (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

802.11 standard 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.