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CCNA 4 v3.0 Module 1Scaling IP Addresses

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Purpose of This PowerPoint

• This PowerPoint primarily consists of the Target Indicators (TIs) of this module in CCNA version 3.0.

• 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

• Scaling networks with Network Address Translation and Port Address Translation

• Dynamic Host Configuration Protocol

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Private Addressing

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NAT

• A NAT-enabled device typically operates at the border of a stub network.

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NAT Terms

• Inside Local Addresses – An IP address assigned to a host inside a network. This address is likely to be a RFC 1918 private address.

• Inside Global Address – A legitimate IP address assigned by the NIC or service provider that represents one or more inside local IP address to the outside world.

• Outside Local Address - The IP address of an outside host as it known to the hosts in the inside network.

• Outside Global Address - The IP address assigned to a host on the outside network. The owner of the host assigns this address.

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NAT Features

• Static NAT is designed to allow one-to-one mapping of local and global addresses.

• Dynamic NAT is designed to map a private IP address to a public address.

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PAT Features

• PAT uses unique source port numbers on the inside global IP address to distinguish between translations.

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NAT Benefits

• Eliminates re-assigning each host a new IP address when changing to a new ISP

• Eliminates the need to re-address all hosts that require external access, saving time and money

• Conserves addresses through application port-level multiplexing

• Protects network security

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Configuring NAT and PAT

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Configuring NAT

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Configuring PAT

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Verifying NAT and PAT Configuration

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Troubleshooting NAT and PAT

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Issues With NAT

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DHCP

• DHCP works by providing a process for a server to allocate the IP information to clients. Clients lease the information from the server for an administratively defined period.

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BOOTP and DHCP Differences

• DHCP defines mechanisms through which clients can be assigned an IP address for a finite lease period. This lease period allows for re-assignment of the IP address to another client later, or for the client to get another assignment, if the client moves to another subnet. Clients may also renew leases and keep the same IP address.

• DHCP provides the mechanism for a client to gather other IP configuration parameters, such as WINS and domain name.

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Major DHCP Features

• Automatic Allocation

• Manual Allocation

• Dynamic Allocation

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DHCP Operation

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The Order of DHCP Messages Transmitting

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Configuring DHCP

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Configuring DHCP While Excluding IP

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Verifying DHCP

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Troubleshooting DHCP

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DHCP Relay