Concept Guide

Until Release 9.3(0.0), ACL supports classication based on the below TCP ags:

• ACK

• FIN

• SYN

• PSH

• RST

• URG

You can now use the ‘ecn’ match qualier along with the above TCP ag for classication.

The following combination of match qualiers is acceptable to be congured for the Dell EMC Networking OS software through L3 ACL

command:

• Classication based on DSCP only

• Classication based on ECN only

• Classication based on ECN and DSCP concurrently

You can now use the set-color yellow keyword with the match ip access-group command to mark the color of the trac as ‘yellow’ would

be added in the ‘match ip’ sequence of the class-map conguration.

By default, all packets are considered as ‘green’ (without the rate-policer and trust-diserve conguration) and hence support would be

provided to mark the packets as ‘yellow’ alone will be provided.

By default Dell EMC Networking OS drops all the ‘RED’ or ‘violate’ packets.

The following combination of marking actions to be specied match sequence of the class-map command:

• set a new DSCP for the packet

• set the packet color as ‘yellow’

• set the packet color as ‘yellow’ and set a new DSCP for the packet

This marking action to set the color of the packet is allowed only on the ‘match-any’ logical operator of the class-map.

This marking-action can be congured for all of the below L3 match sequence types:

• match ip access-group

• match ip dscp

• match ip precedence

• match ip vlan

Sample conguration to mark non-ecn packets as “yellow”

with single trac class

Consider the use case where the packet with DSCP value “40” need to be enqueued in queue#2 and packets with DSCP value as 50 need

to be enqueued in queue#3. And all the packets with ecn value as ‘0’ must be marked as ‘yellow’.

The above requirement can be achieved using either of the two approaches.

Approach without explicit ECN match qualiers for ECN packets:

ip access-list standard dscp_50

Quality of Service (QoS)

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