A subnetwork or subnet is a logical subdivision of an IP network. The practice of dividing a network into two or more networks is called subnetting.
- Devices in the same subnet share the same network number or routing prefix
- In technical terms this is known as the most significant bit-group in their IP Addresses
- In layman terms this can also be considered the network ID
- The the second field (suffix) is considered the rest field or host identifier
- The routing prefix may be experessed in
Classless Inter-Domain Routing (CIDR)
+ Example:
198.51.100.0/24or2001:db8::/32 - For IPv4 a network may be characterized by
its subnet mask or netmask:
- This is the bitmask that when
applied by a bitwise AND
operation to any IP address in the network, yields the routing prefix.
- Usually expressed in dot-decimal notation.
For example:
255.255.255.0is the subnet mask for the prefix198.51.100.0/24
- Usually expressed in dot-decimal notation.
For example:
- This is the bitmask that when
applied by a bitwise AND
operation to any IP address in the network, yields the routing prefix.
Network addressing and routing#
STUB
IPv4#
Determining the network prefix#
See Subnet Mask
Subnetting#
See Subnetting
References#
https://en.wikipedia.org/wiki/Subnetwork