An Implementation of Variable Length Subnetting

This an example of how an variable subnetting can be implemented since not all departments in a company have the same number of hosts so based on the need the length of the sub-networks must vary to use the IP's efficiently.

Example:

Company Acme, Inc. has just received a class C IP address space for use in their new computer
network (192.168.100.0/24). As a network engineer for Acme, Inc. you have to design an
addressing scheme that divides this address space into multiple subnets as per the following
requirements:

• There are four departments (Management, Sales, Engineering, and IT) and each of the departments must be allocated a separate IP subnet.
• The Management subnet will contain no more than 10 computers.
• The Sales subnet will contain no more than 45 computers.
• The Engineering subnet will contain no more than 115 computers.
• The IT subnet will contain no more than 20 computers.

First, design an addressing scheme that satis es these requirements. Answer by lling in the
table below. Specify both the netmask and its pre x length. How many addresses can be used
for computers on each subnet given the fact that one address must be reserved for the default
gateway?

 

Next, refer to the gure on the next page. Assume that, on each subnet, the default gateway
address is the lowest usable address on that subnet. Assign a valid IP address for each interface
shown in the gure and ll in the con guration parameters as required. (IP stands for IP Address;
Mask stands for Subnet Mask; and GW stands for Default Gateway Address. The four addresses
attached to the links from the router to the switches belong to the router's interfaces). It does
not matter what addresses you assign to the workstation interfaces, as long as they are valid
addresses for that subnet.

 

Answers: 

The things to be noted here are the various segments have different subnet address so helps to route uniquely,Here the Class C IP Address is split as 32,32,64,128 Since there is a greater need at Engineering Department and lesser in Management and sales.

 

 

for understanding basics of subnetting :https://computer-lords.blogspot.in/2017/10/network-addressing-ipv4-basic.html