Asus WL-100gE - Manual (Page 49)

ASUS WLAN Card 49
Chapter 5
Chapter 5 - Glossary
Glossary
Wireless mobile clients receiving a direct-sequence transmission use the spreading
code to map the chips within the chipping sequence back into bits to recreate the original
data transmitted by the wireless device. Intercepting and decoding a direct-sequence
transmission requires a predefined algorithm to associate the spreading code used by
the transmitting wireless device to the receiving wireless mobile client.
This algorithm is established by IEEE 802.11b specifications. The bit redundancy within
the chipping sequence enables the receiving wireless mobile client to recreate the original
data pattern, even if bits in the chipping sequence are corrupted by interference. The
ratio of chips per bit is called the spreading ratio. A high spreading ratio increases the
resistance of the signal to interference. A low spreading ratio increases the bandwidth
available to the user. The wireless device uses a constant chip rate of 11Mchips/s for all
data rates, but uses different modulation schemes to encode more bits per chip at the
higher data rates. The wireless device is capable of an 11 Mbps data transmission rate,
but the coverage area is less than a 1 or 2 Mbps wireless device since coverage area
decreases as bandwidth increases.
Encryption
This provides wireless data transmissions with a level of security. This option allows
you to specify a 64-bit or a 128-bit WEP key. A 64-bit encryption contains 10 hexadecimal
digits or 5 ASCII characters. A 128-bit encryption contains 26 hexadecimal digits or 13
ASCII characters.
64-bit and 40-bit WEP keys use the same encryption method and can interoperate on
wireless networks. This lower level of WEP encryption uses a 40-bit (10 hexadecimal
digits assigned by the user) secret key and a 24-bit Initialization Vector assigned by the
device. 104-bit and 128-bit WEP keys use the same encryption method.
All wireless clients in a network must have identical WEP keys with the access point to
establish connection. Keep a record of the WEP encryption keys.
Extended Service Set (ESS)
A set of one or more interconnected basic service set (BSSs) and integrated
local area networks (LANs) can be configured as an Extended Service Set.
ESSID (Extended Service Set Identifier)
You must have the same ESSID entered into the gateway and each of its wireless
clients. The ESSID is a unique identifier for your wireless network.
Ethernet
The most widely used LAN access method, which is defined by the IEEE 802.3 standard.
Ethernet is normally a shared media LAN meaning all devices on the network segment
share total bandwidth. Ethernet networks operate at 10Mbps using CSMA/CD to run
over 10-BaseT cables.