Survey of Wireless Networking
Radio Frequency - RF
Security and Encryption
WEP (Wired Equivalency Privacy)
40bit,64 bit
128 bit
Protocol Encryption (SSL, PKI, etc.)
Frequency Hopping
Service Set Identifier
Notes:
Wireless Encryption Protocol (WEP)
"40-bit" vs. "64-bit"
WEP takes three bytes from the 802.11b header and combines it with a user defined five-byte sequence for a total of eight bytes or 64 bits. When a vendor describes encryption as "40-bit" they are referring to the user-supplied key. If a vendor claims "64-bit" encryption they are referring to the whole 8 byte sequence (user and header) used for encryption. The upshot is they are referring to the same level of encryption. Some people would suggest that the representation is between the hexidecimal and decimal representation of the numbers (40Hex is 64 Decimal) - they would be wrong.
Frequency Hopping techniques spread transmissions over a series of up to 79 channels and the frequencies rotate many times a second for a fixed period of time before moving on to the next channel. Without knowing the frequency dwell time and the hopping pattern, it is impossible for a non-participating station to decode the signal.
Service Set Identifier. This number is a large number (32 characters) which must be known before a station can begin to participate in a wireless network. Usually this is in an ESS type configuration (AKA an Infrastructure type network)