SNR S2989G-48TX-DC [375/553] And dscp value according to pass through cos pass through dscp

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S2989G-24TX Operation Manual

Chapter 6 Security Function Configuration

6-102

buffer is

available

Yes

Read the buffer value according

to the queue management

algorithm(WDRR/SP), the drop

precedence and the egress

queue

Start

Remark DSCP and L2 COS fields

of the packets according to

Int-Prio-to-DSCP

Int-Prio-to-COS mapping(*1)

Select the queue according to

IntPrio-to-Queue mapping

Obtain the packet Drop-Prec

according to IntPrio-to-Drop-

Prec

Queuing and scheduling: There are the internal priority for the egress packets, the

scheduling operation assigns the packets to different priority queues according to the

internal priority, and then forward the packets according to the priority queue weight and

the drop precedence. The following flowchart describes the scheduling operation.

Figure 6-40 Queuing and Scheduling process

Note 1: The ingress configures pass-through-cos, pass-through-dscp to forbid the

rewrite of L2 CoS priority and dscp value. At the egress, obtain L2 CoS priority and dscp

value according to the final Int-Prio of the packets, decide whether rewrite L2 CoS priority

and dscp value according to pass-through-cos, pass-through-dscp.

6.12.2

QoS Configuration Task List

Configure class map

Drop the

packets

Finish

Place the packets into the

specified queue, and forward the

packets according to the weight

priority