Operating instructions

Glossary
Industrial Ethernet SCALANCE X-100 and SCALANCE X-200 Product Line
Glossary-2 Operating instructions, 09/2006, A5E00349864 Release 7
Cut through
With this technique, a frame is forwarded as soon as the destination address is recognized.
The delay is therefore not dependent on the frame length. If there are problems in a network,
however, defective frames are also forwarded and can therefore add to the network load.
Default gateway
A network node that forwards all frames not addressed to stations in the same LAN (subnet).
DHCP
DHCP (Dynamic Host Configuration Protocol), like BOOTP, a method for automatic
assignment of IP addresses. With DHCP, however, addresses can be assigned while the
device is operating.
Event
For Alarms & Events: An event is anything that happens that could be of interest to a client.
Although events can also be generated when a condition is met, they are not necessarily
dependent on conditions. Events that are not linked to conditions include, for example, error
messages of the communication system.
Fault mask
Specifies the desired status (good status). Deviations from this occurring during operation
are handled as faults.
IRT
Isochronous Real Time supports applications with extremely high real-time requirements (for
example, motion control).
MIB
Managed Information Base. A tree structure containing all the data relevant for network
management in SNMP.
Mirroring
A port (mirror port) with its specific data traffic can be mirrored to another port (monitor port)
for test purposes. Protocol analysis devices can be connected to the monitor port, in other
words, the monitor port is not available for data exchange. Mirroring has no effect on the
mirror port.
Multicast
A frame with a multicast address is received by all nodes prepared to receive this address.