Avaya P3343T-ML manual About Multilayer Policy

Chapter 11 Avaya P330 Layer 2 Features

Multilayer Policy

Multilayer Policy is a set of features for enforcing QoS and Access Control policy on routed and switched packets. One of its major goals is supporting Differentiated Services for Avaya VoIP solutions.

About Multilayer Policy

Multilayer Policy is enforced on the 10/100 Mbps ports of a P334T-ML module. In general, Multilayer Policy consists of the following parts:

•Policy Lists — groupings of Access lists, DSCP-to-COS maps, and Trust mode attributes.

•Access Lists — ordered lists of classification rules applied to frames received and action pairs determining how they are to be handled.

•DSCP-to-COS Maps — mapping function that set the frame 802.1p priority according to its DSCP value.

•Trust Modes — policy-list attribute; either “untrusted,” “trust-COS,” or “trust-DSCP.”

Access Lists

Access Lists (ACL) are at the center of Multilayer Policy. Typically, users specify their classification demands by defining Access Lists. An Access List is an ordered list of classification rules and actions. For each frame received by the system, the Multilayer Policy application tries the classification rules—one-by-one—and executes the action associated with the first rule that matches.

Rules are based on the following properties:

•IP:IP version 4 packets with specific source and destination addresses (+ wildcards)

•IP version 4 packets with a specific protocol number – 0 to 255 – with specific source and destination addresses (+ wildcards).

•TCP:TCP/IPv4 packets with specific source and destination addresses (+ wildcards) and source and destination ports (+port ranges). The keyword “established” enables “permit” for TCP packets with “ack” flag set. E.g., this will not allow matching packets that open TCP connections.

•UDP:UDP/IPv4 packets with specific source and destination addresses (+ wildcards) and source and destination ports (+ port ranges).

Actions supported include:

•permit – allows the packet through

•deny – drops the packet

•deny-and-notify – drops the packet and sends an SNMP trap

•fwd0, fwd1 .... fwd7 – assigns priority to the packet

Avaya P334T-ML User’s Guide 111