Glossary
5-4-3 Rule
See
“
repeater rule
”
AUI
Attachment Unit Interface. 10 Mbps TP port (15-pin sub D) for connecting an AUI cable (drop
cable). Can be implemented either as DTE (data terminal equipment) or as DCE (data
carrier equipment). Is primarily used for the connection to triax segments.
Autocrossover
Method with which a TP port is automatically switched between MDI and MDI-X assignment
to establish a connection independently of the port assignment of the device to be
connected. This ensures that crossover cables are not required. The autocrossover function
requires that the respective port is set to autonegotiation mode.
Autonegotiation
Method standardized according to IEEE 802.3 with which transmission parameters (e.g.
10/100
Mbps, full / half duplex) between devices are automatically negotiated.
C-PLUG
The C-PLUG (configuration plug) is a swap medium for backing up the configuration data. If
the device is replaced, the configuration can be applied by exchanging the C-PLUG.
CRC
Cyclic Redundancy Check. A checksum used in transmission protocols to detect errors in
frames.
Cut Through
With this method, a frame is forwarded as soon as the destination address is recognized.
Therefore the delay does not depend on the frame length. However, if there are problems in
a network, also defective frames are forwarded which may increase the network load.
Industrial Ethernet Media Converters SCALANCE X-100 Series
Commissioning Manual, 06/2006, A2B00051526A, Product Version 03
Glossary-1
