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Catalyst 2950 Desktop Switch Software Configuration Guide
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Chapter 25 Configuring Network Securi t y w it h ACLs Configuring ACLs

Unsupported Features

The switc h does not support these IOS rout er ACL-related features:
Non-IP protocol ACLs (see Table 25-2 on page 25-8 )
Bridge -group ACLs
IP accoun ting
ACL support on the ou tboun d directi on
Inbound an d outbou nd rate limi ting (except with Q oS ACLs)
IP packets that have a header length of less than 5 bytes
Reflexive ACLs
Dynami c ACLs (ex cept f or cert ain s pecia lized d ynamic A C Ls us ed b y the switc h cl ust ering featur e)
ICMP -bas ed filte ring
Interio r Ga teway Routing Pr otoc ol ( IGM P)-base d filtering

Creating Standard and Extended IP ACLs

This section describes how to create switch IP ACLs. The switch tests packets against the conditions in
an access list one by one. The first match determines whether the switch accepts or rejects the packet.
Because the switch stops testing conditions after the first match, the order of the conditions is critical.
If no c ond itio ns m atch, the switc h deni es the pac ket.
Follow these steps to use ACLs:
Step 1 Create an ACL by specifying an access list number or na me and access cond itions.
Step 2 Apply the ACL to interfaces or terminal lines.
The software supports th ese kinds of IP access lists:
Standard IP access lists use source addresses for matching operations.
Extend ed IP access lists use source and de stination addresses for matching operat ions an d optional
protoc ol-typ e informa tion fo r finer granular ity of con trol.
Note M AC extended acc ess list use sour ce and desti nation MAC addresses and op tional pr otocol type
inform ation fo r matchi ng ope rations. For mo re inform atio n, see the Creating Na med MAC Extended
ACLs sec tion o n p ag e 25-18 .
The next sections describe access lists and the steps for using them.