Transcript CCNA 1 Module 11 TCP/IP Transport and Application Layers

CCNA 2 v3.1 Module 11
Access Control Lists (ACLs)
© 2004 Cisco Systems, Inc. All rights reserved.
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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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To Locate Instructional Resource
Materials on Academy Connection:
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materials created by the instructor community
• Go to the Tools section
• Go to the Alpha Preview section
• Go to the Community link under Resources
• See the resources available on the Class home
page for classes you are offering
• Search http://www.cisco.com
• Contact your parent academy!
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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
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