ProSafe M4100 and M7100 Managed Switches

CoS Queue Mapping

CoS queue mapping uses trusted and untrusted ports.

Trusted Ports

The system takes at face value certain priority designations for arriving packets.

Trust applies only to packets that have that trust information.

There can be only one trust field at a time - per port.

-802.1p user priority (This is the default trust mode and is managed through switching configuration.)

-IP precedence

-IP DiffServ Code Point (DSCP)

The system can assign the service level based upon the 802.1p priority field of the L2 header. You configure this by mapping the 802.1p priorities to one of three traffic class queues. These queues are:

Queue 2. Minimum of 50 percent of available bandwidth

Queue 1. Minimum of 33 percent of available bandwidth

Queue 0. Lowest priority, minimum of 17 percent of available bandwidth

For untagged traffic, you can specify the default 802.1p priority on a per-port basis.

Untrusted Ports

No incoming packet priority designation is trusted; therefore, the default priority value for the port is used.

All ingress packets from untrusted ports, where the packet is classified by an ACL or a DiffServ policy, are directed to specific CoS queues on the appropriate egress port. That specific CoS queue is determined by either the default priority of the port or a DiffServ or ACL-assigned queue attribute.

Used when trusted port mapping is unable to be honored - for instance, when a non-IP DSCP packet arrives at a port configured to trust IP DSCP.

Chapter 11. CoS Queuing 191

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NETGEAR M4100, M7100 CoS Queue Mapping, Trusted Ports, Untrusted Ports, CoS queue mapping uses trusted and untrusted ports