Tag :: TCAM

TCAM features matching on the same packet type and executing the same action are implicitly prioritized if both are

As of DMF-8.9.0, when several IP addresses are used in a single policy (whether via an address group or individually across match rules with otherwise identical conditions), the controller groups the addresses together and programs them as a field set on supported switches. This field set has a label that can be directly referenced by TCAM, which allows that TCAM entry to match against packets with any of the IP prefixes in that field set. This optimization dramatically reduces the TCAM consumption for policies that reference many addresses, allowing significantly more policies or addresses to be programmed without exceeding switch TCAM capacity limits. For example, on a switch incapable of performing this optimization, a policy matching traffic from a 100-entry source address group to a 100-entry destination address group would require 100x100=10,000 individual entries. With this optimization, the controller programs two field sets and a single match rule that references both field sets, reducing TCAM consumption from 10,000 entries to just 1 entry for that policy.

TCAM is an important hardware resource which is used by ACL, Pbr, Qos on 7160 series. There are a total of 8 Tcam banks on

Slice reservation can be used to solve TCAM resources limitations due to suboptimal group order in the TCAM because of the FCFS (First come first serve) nature of the TCAM. The user will be able to reserve a certain amount of entries in the TCAM for a specific feature. The configuration happens through a new keyword in feature mode when configuring a TCAM profile.

This article describes how to configure a TCAM ( Ternary Content Addressable Memory ) profile for ingress filtered mirroring sessions. This profile allows mirroring sessions to use less TCAM resources by individually selecting the allowable match criteria.

This article describes how to customize TCAM ( Ternary Content Addressable Memory ) lookup for each feature which uses TCAM. The lookup is composed of fields, in the packet header / forwarding chip pipeline decisions, that are of interest to a feature. Size of the lookup determines the number of banks to be used by a feature. Traditionally, any feature uses a predefined TCAM lookup.

This article describes a set of CLI commands to create TCAM profiles. The profile is composed of a set of TCAM features, with each feature having customized lookup key, actions and packet types to hit.