Specifications

Glossary
SCALANCE X-400 BA
Operating Instructions, 03/2009, C79000-G8976-C186-07
151
HSR
→ High Speed Redundancy
Latency
Latency specifies the time taken by frames to pass through a switch. This does not include
the time required for buffering frames.
Load containment
With its filtering functions, a switch makes sure that local data traffic remains local. The local
network load of a segment is contained in the originating segment and does not represent
extra load on the remainder of the network.
MDI
Medium Dependent Interface, - straight.
On a MDI port or a MDI cable, the receive (Rx)
and the send (Tx) lines are not crossed over
MDI-X
Medium Dependent Interface – crossover.
On an MDI-X port or MDI-X cable, the receive (Rx) and the send (Tx) lines are crossed over.
Media redundancy
Method for increasing availability in Industrial Ethernet networks in which devices can be
reached over different paths. This might be achieved by meshing networks, arranging
parallel transmission paths or by closing a linear bus topology to form a ring.
Media redundancy within a ring topology is available with SIMATIC NET products with the
►HSR and ►MRP methods.
Media Redundancy Protocol
A method specified in the IEC 61158 Type 10 standard for increasing network availability in
a ring topology.
See also ►media redundancy.
MIB
Management Information Base. The MIB is a formal description of network objects in the
form of a tree structure that contains all the relevant information for network management in
SNMP.