User Documentation
Glossary
2053260000/05/2015
147
4 Glossary
Industrial Ethernet has brought with it new specialist terminology. Some of the
most important terms are briey explained here.
4B/5B
A block coding diagram for FDDI and ATM. With 4B/5B coding, all data is
divided into 4-bit units (a nibble) and recoded into 5-bit units (symbols) following
a table.
10BaseT
Ethernet standard permitting a 10 Mbit/s transmission
10BaseFL
10 Mbit/s Ethernet via bre-optic cabling
100BaseFX
100 Mbit/s Fast Ethernet via bre-optic cable
100BaseSX
100 Mbit/s Fast Ethernet – identical to operations in 100BaseFX, but a 850 nm
bre-optic technology is used
100BaseTX
100 Mbit/s Fast Ethernet system via twisted-pair cables
802.1x
This is an authentication standard for VLAN or WLAN networks. It uses an
authentication server which contains all PC login data with authorised access
to the network. Users log on to the server with their normal login data and if the
information (name and password) is correct, the connection to the network is
enabled.
This standard is often used in universities to allow students to connect to the
network without knowing the network key.
AUI (Attachment Unit Interface)
Interface between the transceiver and network card
Auto-negotiation
Auto-negotiation describes a process which allows network cards to
independently recognise the correct transmission speed and the duplex
procedure of the network port to which they are connected and to congure
themselves accordingly.