How to Subnet Using VLSM

Step-by-Step Guide

1. 1

   Step 1: List all of your possible subnets.

   /24 = 254 hosts /25 = 126 hosts /26 = 64 hosts /27 = 32 hosts /28 = 16 hosts /29 = 6 hosts /30 = 2 hosts
2. 2

   Step 2: Arrange your requirements in descending order.

   Subnet A
   - 66 Subnet C
   - 22 Subnet B
   - 10 Subnet D
   - 2 , Allocate the First highest subnet Assign
   192.168.10.20 mask /25 for subnet A to satisfy there need for 66 hosts.
   
   The last octet of the subnet mask will be 1000000 (255.255.255.128) Assign the next highest subnet Assign
   192.168.10.128 the mask /27 for subnet C; the last octet of the subnet mask will be 11100000 (255.255.255.224) Assign the next highest subnet Assign
   192.168.10.160 the mask /28 for subnet B; the last octet of the subnet mask will be 11110000 (255.255.255.240) Assign the last subnet Assign
   192.168.10.176 the mask /30 for subnet D; the last octet of the subnet mask will be 11111100 (255.255.255.252). , Subnet A =
   192.168.10.0/25 ~126 hosts (needed 66) Subnet C =
   192.168.10.128/27 ~ 30 hosts (needed 22) Subnet B =
   192.168.10.160/28 ~ 14 hosts (needed 10) Subnet D =
   192.168.10.176/30 ~ 2 hosts (needed 2)
3. 3

   Step 3: Assign the appropriate subnet masks to each subnet.

4. 4

   Step 4: Review the Subnetting summary.

Detailed Guide

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