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Summary Module 1

Summary Module 1

Before students begin Module 2, they must be able to explain the concepts of NAT, PAT, and DHCP.
Online assessment options include the end-of-module online quiz in the curriculum and the online Module 1 exam. From memory, students should be able to fill in Drag and Drop assessments for Basic NAT Operation and NAT with Overload. Students should also be able to complete a Checkbox activity for the advantages and disadvantages of NAT.
A comprehension of the following key points should have been achieved:
  • Private addresses are for private, internal use and should never be routed by a public Internet router.
  • NAT alters the IP header of a packet so that the destination address, the source address, or both addresses are replaced with different addresses.
  • PAT uses unique source port numbers on the inside global IP address to distinguish between translations.
  • NAT translations can occur dynamically or statically and can be used for a variety of uses.
  • NAT and PAT may be configured for static translation, dynamic translation, and overloading.
  • The process for verifying NAT and PAT configuration includes the clear and show commands.
  • The debug ip nat command is used for troubleshooting NAT and PAT configuration.
  • NAT has advantages and disadvantages.
  • DHCP works in a client/server mode. This enables clients to obtain IP configurations from a DHCP server.
  • BOOTP is the predecessor of DHCP and shares some operational characteristics with DHCP. However, BOOTP is not dynamic.
  • A DHCP server manages pools of IP addresses and associated parameters. Each pool is dedicated to an individual logical IP subnet.
  • The DHCP client configuration process has four steps.
  • A DCHP server is usually configured to assign more than IP addresses.
  • The show ip dhcp binding command is used to verify DHCP operation.
  • The debug ip dhcp server events command is used to troubleshoot DHCP.
When a DHCP server and a client are not on the same segment and are separated by a router, the ip helper-address command is used to relay broadcast requests. 

 An understanding of the following key points should have been achieved:
  • Private addresses are for private, internal use and should never be routed by a public Internet router.
  • NAT alters the IP header of a packet so that the destination address, the source address, or both addresses are replaced with different addresses.
  • PAT uses unique source port numbers on the inside global IP address to distinguish between translations.
  • NAT translations can occur dynamically or statically and can be used for a variety of uses.
  • NAT and PAT may be configured for static translation, dynamic translation, and overloading.
  • The process for verifying NAT and PAT configuration include the clear and show commands.
  • The debug ip nat command is used for troubleshooting NAT and PAT configuration.
  • NAT has advantages and disadvantages.
  • DHCP works in a client/server mode, enabling clients to obtain IP configurations from a DHCP server.
  • BOOTP is the predecessor of DHCP and shares some operational characteristics with DHCP, but BOOTP is not dynamic.
  • A DHCP server manages pools of IP addresses and associated parameters. Each pool is dedicated to an individual logical IP subnet.
  • The DHCP client configuration process has four steps.
  • Usually, a DCHP server is configured to assign more than IP addresses.
  • The show ip dhcp binding command is used to verify DHCP operation.
  • The debug ip dhcp server events command is used for troubleshooting DHCP.
When a DHCP server and a client are not on the same segment and are separated by a router, the ip helper-address command is used to relay broadcast requests. 

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