Qos/Priority; Description Of Prioritization - Hirschmann RS20 User Manual

Network Load Control

8.4 QoS/Priority

8.4.1

Description of Prioritization

This function prevents time-critical data traffic such as language/video or
real-time data from being disrupted by less time-critical data traffic during
periods of heavy traffic. By assigning high traffic classes for time-critical data
and low traffic classes for less time-critical data, this provides optimal data
flow for time-critical data traffic.
The device supports 4 (8 with MACH 4000, MACH 104, MACH 1040 and
PowerMICE) priority queues (traffic classes according to IEEE 802.1D).
assignment of received data packets to these classes is performed by
the priority of the data packet contained in the VLAN tag when the
receiving port was configured to "trust dot1p".
the QoS information (ToS/DiffServ) contained in the IP header when the
receiving port was configured to "trust ip-dscp".
the port priority when the port was configured to "no trust".
the port priority when receiving non-IP packets when the port was
configured to "trust ip-dscp".
the port priority when receiving data packets without a VLAN tag
page 73 "Configuring the Ports")
"trust dot1p".
Default setting: "trust dot1p".
The device considers the classification mechanisms in the sequence shown
above.
Data packets can contain prioritizing/QoS information:
VLAN priority based on IEEE 802.1Q/ 802.1D (Layer 2)
Basic Configuration
Release 6.0 07/2010
and when the port was configured to
8.4 QoS/Priority
The
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