Accton Technology ES4710BD manual Star, Finish

ES4710BD 10 Slots L2/L3/L4 Chassis Switch

Star

Trust CoS value (IP & non-IP packets)

Reads ingress classification Trust DSCP value (IP packets) configuration info

Trust IP priority

IP & non-IP (IP packets) packets

Generates interior DSCP value consistent with the DSCP value carried in packet header

Interior DSCP value

generated according to IP

Precedence value and

IP-Precedence-to-DSCP mapping of the packet

(optional) Defines

DSCP-to-DSCP

mutation map

QoS ACLs configured

at ingress?

Matching permit

entries?

Generates DSCP value

specified by ACLs

Finish

Generate default internal

DSCP value (0)

CoS value carried with

packet?

Internal DSCP according to default CoS value and Cos-to-DSCP mapping

Internal DSCP according to

packet CoS value and Cos-to-DSCP mapping

Finish Finish

Fig 16-4 Classification process

Policing and remark: Each packet in classified ingress traffic is assigned an internal DSCP value and can be policed and remarked.

Policing can be performed based on DSCP value to configure different policies that allocate bandwidth to classified traffic. If the traffic exceeds the bandwidth set in the policy (out of profile), the out of profile traffic can be allowed, discarded or remarked. Remarking uses a new DSCP value of lower priority to replace the original higher level DSCP value in the packet; this is also called “marking down”. The following flowchart describes the operations during policing and remarking.

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