Appendix
BAT54-Rail/F..
Release
 
7.54
 
06/08
13.5
 
Glossary
529
13.5Glossary
802.11 Wireless LAN specification of the IEEE; data rate up to 2 Mbps; in 2.4 GHz ISM band; 
FHSS and DSSS; infrared spectrum communications also planned
802.11a Extension to 802.11; data rate up to 54 Mbit/s; in 5 GHz band; OFDM
802.11b Extension to 802.11; data rate up to 11 Mbit/s; in 2.4 GHz band; high market penetration; 
DSSS/CCK
802.11g Extension to 802.11; data rate up to 54 Mbit/s; in 2.4 GHz band; OFDM and DSSS
802.11h 802.11a customization, data rate up to 54 Mbit/s; in 5 GHz band; in area of transmission 
power and frequency management; for use in Europe; OFDM
802.11i Future 802.11 extension with additional security features
802.1x Specification of a port-based authentication mechanism from the IEEE
AES Advanced Encryption Standard
Access point Base station in a wireless LAN; independent LAN-WLAN bridge; connects stations of a 
LAN (local network) with a WLAN (wireless network) in a point-to-multipoint mode; con-
nects two networks over a wireless network in point-to-point mode
Access router Active network component for connection of a local network to the Internet or a company 
network
ADSL Asymmetrical Digital Subscriber Line - transmission process for high-speed data trans-
mission over normal telephone lines. With ADSL, transmissions (downstream) of up to 6 
Mbps can be implemented over normal telephone lines; for bidirectional transmission 
there is a second frequency band with transmission speeds of up to 640 kbps (upstream) 
- hence the name "asymmetric". 
Bandwidth Data rate with which a user can surf the Internet; the higher the bandwidth, the faster the 
connection
Broadband Service which provides high bandwidth; e.g.: DSL or WLAN
Bridge Transport protocol-independent, transparent network component; transmits all packets 
which are identified as "not local" and only understands the difference between "local" 
and "remote". Works on Layer 2 of the OSI model
Broadcast Broadcasts are packets to all stations of a local network; bridges transmit broadcasts; 
routers do not transmit broadcasts
BSS Basic Service Set
CAPI Common ISDN Application Programming Interface - CAPI is a standard for control of 
ISDN adapters
CCK Code Complementary Keying; type of modulation used by DSSS
Client Any computer equipped with a wireless LAN adapter (wireless LAN card), which uses 
services provided by other participants in the wireless network
CSMA/CA  Carrier Sense Multiple Access with Collision Avoidance; access procedure to the radio 
channel used under 802.11
CRC Cyclic Redundancy Check; process for detecting bit errors
Data throughput Speed at which you can surf on the Internet; depends on the bandwidth and the number 
of users
DHCP Dynamic Host Configuration Protocol 
DNS Domain Name Service - computers communicate with computers in remote networks 
using IP addresses; DNS servers translate names into IP addresses; without DNS serv-
ers, you would have to remember all IP addresses and couldn't work with names (e.g. 
www.hirschmann.com)