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CCNA 2 v3.1 Module 11 Access Control Lists (ACLs)

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Purpose of This PowerPoint

• This PowerPoint primarily consists of the Target Indicators (TIs) of this module in CCNA version 3.1.

• It was created to give instructors a PowerPoint to take and modify as their own.

• This PowerPoint is:NOT a study guide for the module final assessment.NOT a study guide for the CCNA certification exam.

• Please report any mistakes you find in this PowerPoint by using the Academy Connection Help link.

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Objectives

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What are ACLs?

• ACLs are lists of conditions used to test network traffic that tries to travel across a router interface. These lists tell the router what types of packets to accept or deny.

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How ACLs Work

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Protocols with ACLs Specified by Numbers

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Creating ACLs

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The Function of a Wildcard Mask

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Verifying ACLs

• There are many show commands that will verify the content and placement of ACLs on the router.

show ip interface

show access-lists

Show running-config

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Standard ACLs

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Extended ACLs

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Named ACLs

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Placing ACLs

• Standard ACLs should be placed close to the destination.

• Extended ACLs should be placed close to the source.

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Firewalls

A firewall is an architectural structure that exists between the user and the outside world to protect the internal network from intruders.

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Restricting Virtual Terminal Access

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Summary