Subnetting - dejanu/linux GitHub Wiki

Subnetting = create smaller broadcast domains in order to reduce the size of the network

SLSM = Same Length Subnet Mask
VLSM = Variable Length Subnet Mask

• reduces overall network traffic
• improves network performance
• implement security policy (which subnets are allowed to communicate together)

!!! Every interface on a router is connected to a network. The IP and the mask from each interface is used to specify a broadcast domain.

IPV4 subnets are created using one or more of the HOST bits as NETWORK bits ->
Imprumutam unu sau mai multi biti din pardea de HOST si il folosim ca bit de NETWORK(retea)

**Classful Subnets Mask **

1. Class A /8 2^24=16.777.214 hosts in one broadcast domain
   255.0.0.0 = N.H.H.H

2. Class B /16 2^16=65.534 hosts in one broadcast domain
   255.255.0.0 = N.N.H.H

3. Class C /24 2^8 - 2 = 254 hosts in one broadcast domain
   255.255.255.0 = N.N.N.H