Bogon networks are invalid on the internet, as they are networks that have been reserved for special use, or have not yet been allocated to a customer. These networks should not be seen on the internet.

Some examples of reserved IPv4 networks are:

• Private Networks (10.0.0.0 /8, 172.16.0.0 /12, and 192.168.0.0 /16)
• Loopback Addresses (127.0.0.0 /8, ::1 /128)
• Link-local Addresses (169.254.0.0 /16, FE80:: /10)
• Initialisation Addresses (0.0.0.0 /8)

In addition to these addresses, any blocks of networks that IANA has not yet assigned to RIR’s is considered a bogon network.