1 / 14

Variable Length Subnetting

Variable Length Subnetting. Jim Blanco Aparicio-Levy Technical Center. Variable Length Subnetting. VLSM allows us to use one class C address to design a networking scheme to meet the following requirements: Perth 60 users Kula Lumpur 28 users Sydney 12 users Singapore 12 users

Télécharger la présentation

Variable Length Subnetting

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Variable Length Subnetting Jim Blanco Aparicio-Levy Technical Center

  2. Variable Length Subnetting • VLSM allows us to use one class C address to design a networking scheme to meet the following requirements: • Perth 60 users • Kula Lumpur 28 users • Sydney 12 users • Singapore 12 users • WAN links between each router

  3. Networking Requirements Kula 60 WAN 2 WAN 2 WAN 2 Sydney 60 Sing. 60 Perth 60 • Classful subnetting is very wasteful. • In the example above, a /26 was used to provide the 60 addresses for Perth and the other LANs. There are no addresses left for WAN links

  4. VLSM • Forget everything you learned about classfull subnetting. • Just remember you have 256 – 2 = 254 addresses to work with.

  5. VLSM List your network requirements in descending order.

  6. VLSM Calculate the subnet mask to meet largest requirement - Perth

  7. VLSM Keep track of subnet and broadcast addresses. Use the next available Address .64 to calculate a subnet mask for the next largest requirement - Kula Lumpur.

  8. VLSM Sydney needs 12 addresses. Use the next available address .96 to calculate a subnet for Sydney’s requirement for 12

  9. VLSM Singapore also requires 12

  10. VLSM WAN links require 2 addresses each

  11. VLSM

  12. VLSM The networking problem is solved

  13. Networking Scheme Kula 192.168.10.64/27 WAN 192.198.10.133 and 134 WAN 192.198.10.129 and 130 WAN 192.198.10.137 and 138 Sydney 192.168.10.96/28 Sing. 192.168.10.112/28 Perth 192.168.10.0/26 Apply the address to the LAN or WAN link

  14. VLSM • A class C address such as 192.168.12.0 contains 256 - 2 = 254 usable addresses • You used only addresses .0 - .139

More Related