Subnetting can be performing in 2 ways.

FLSM (Fixed Length Subnet Mask)

VLSM (Variable Length Subnet Mask)

Subnetting can be based on requirements.

Requirement of Hosts? 2k-2>=requirement

Requirement of Networks 2n>=requirement

H=host bits N=Networks bits

What we do in Subnetting?

Converting Host bits into Network Bits (reducing no. of hosts bits)

I.E. Converting 0's in 1's.

What is FLSM/CIDR and VLSM?

· Fixed length subnet mask subnetting (FLSM), all students are of equal size and have equal no. of hosts, If in d/f networks,

· VLSM the size is variable and it can have variable no. of hosts thus making the IP addressing more efficient by allowing a routed system of d/f mask length to suit the requirement.

· FLSM is preferred for private IP addresses while for public IP addresses VLSM is the best option.

· Classless Inter-Domain Routing (CIDR /Slash value) is a method for allocating IP addresses and for IP routing. The Internet Engineering Task Force Introduced CIDR in 1993 to replace this previous class-full network addressing architecture on the internet.