Avaya P334T-ML, Installation And Configuration Manual

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Chapter 11 Avaya P330 Layer 2 Features
112 Avaya P334T-ML User’s Guide
DSCP-to-COS Maps
DSCP-to-COS maps set the frame 802.1p priority according to the DSCP priority
value. For each DSCP value, the map contains a corresponding COS. The map
changes the COS value for frames that match an active Access List rule with a
“permit” action.
The following conditions apply to DSCP-to-COS maps:
•
DSCP-to-COS maps are defined within the Policy Lists.
• Only packets that match an Access List rule with a “permit” action can be
modified based on a DSCP-to-COS map.
• Actions supported per DSCP include: Fwd 0, Fwd1 ....Fwd7, Forward no
change.
Trust Modes
P334T-ML supports the following Trust Mode values:
•
“untrusted” — forwards the packet with 802.1p priority=0.
• “trust-cos” — forwards the packet with its original 802.1p priority (default).
• “trust-dscp” — forwards the packet with an 802.1p priority obtained from the
DSCP-to-COS mapping table.
Multilayer Policy Implementation in the P334T-ML
Each P334T-ML can store up to 20 Policy Lists. These lists consist of: Access Lists,
DSCP-to-COS Maps, and Trust Modes.
Avaya P334T-ML supports two policy types:
•
“Router” – the switch enforces the active Policy List only on routed packets.
This applies to P334T-ML switches in “Router” device mode.
• “All” – the switch enforces the active Policy List on all packets that enter
through the Fast Ethernet ports. This applies to P334T-ML switches in “Router”
or “Layer2” device mode.
“All” is the policy type available when the P334T-ML device mode is “Layer2.”
There can be only one active Policy List per module with either policy type.
The following conditions apply to Policy Lists:
•
Policy Lists can be defined in the “switch” context when the P334T-ML is in
“Layer2” device-mode or in the “router” context when the P334T-ML is in
“Router” device-mode.
• Policy Lists are shared by Layer 2 and Layer 3 applications.
• The maximum number of rules per L3 Access List is 9999 when the policy type
is “Router”. If the Policy List is to be applied to Layer 2 as well – policy type
“all”, the maximum number of rules per list is 254.