Comtrend Corporation VI-3223u, User Manual

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5.7 Quality of Service (QoS)
NOTE : QoS must be enabled in at least one PVC to display this option.
(See Appendix G - Connection Setup Appendix G - Connection Setup for
detailed PVC setup instructions).
5.7.1 Queue Management Configuration
To Enable QoS tick the checkbox and select a Default DSCP Mark.
Click
Apply/Save to activate QoS.
QoS and DSCP Mark are defined as follows:
Quality of Service (QoS): This provides different priority to different users or data
flows, or guarantees a certain level of performance to a data flow in accordance with
requests from Queue Prioritization.
Default Differentiated Services Code Point (DSCP) Mark: This specifies the
per hop behavior for a given flow of packets in the Internet Protocol (IP) header that
do not match any other QoS rule.
Select Default DSCP Mark:
The six most significant bits of the DiffServ field is called as the DSCP (Differentiated
Services Code Point). The last two Currently Unused (CU) bits in the DiffServ field
were not defined within the DiffServ field architecture; these are now used as
Explicit Congestion Notification (ECN) bits. Routers at the edge of the network
classify packets and mark them with either the IP Precedence or DSCP value in a
Diffserv network. Other network devices in the core that support Diffserv use the
DSCP value in the IP header to select a PHB behavior for the packet and provide the
appropriate QoS treatment.