Subnetting Basics

Benefits of subnetting include:

• Reduced network traffic
• Optimized network performance
• Simplified management
• Facilitated spanning of large geographical distances.

How To Create Subnets

Take bits from the host portion of the IP address and reserve the to divine the subnet address.


Understanding the Powers of 2


Subnet Masks

• Used to define which part of the host address will be used as the subnet address.
• A 32-bit value that allows the recipient of IP packets to distinguish the network ID portion of the IP address from the host ID portion.

Default Subnet Masks


Classless Inter-Domain Routing (CIDR)

Used to allocate an amount of IP address space to a given entity (company, home, customer, etc).
Example: 192.168.10.32/28

The slash notation (/) means how many bits are turned on (1s) and tells you what your subnet mask is.

CIDR Values