Network Tip: Private Internet Addresses (RFC 1918)

If you have a home router, you probably are familiar with the 192.168.x.x network; this is one of the 3 reserved blocks of private addresses as specified under RFC 1918.

The reserved private address blocks are as follows:

10.0.0.0 - 10.255.255.255 (10/8 prefix)
172.16.0.0 - 172.31.255.255 (172.16/12 prefix)
192.168.0.0 - 192.168.255.255 (192.168/16 prefix)

Private addresses are non-routable (i.e. not used on the Internet) addresses.