What is the origin of the private network address 192.168.*.*?

Solution 1:

Before classless networks were invented, it was decided to make three ranges of private addressing space. These were:

• Class A: 10/8 (the old ARPA reservation)
• Class B: 172.16/12 (one of the first available class Bs)
• Class C: 192.168/16 (one of the first available class Cs)

There are:

• 1 Class A private prefixes (16.7 million addresses)
• 16 Class B privates (65536 addresses each, totalling ~1 million addresses)
• 256 Class C privates (256 addresses each, totalling 65536 addresses)

It is important to note that "Classes" haven't existed since 1994, and these days we use CIDR, which has a variable length subnet mask.

Solution 2:

It appears they where selected by IANA simply because they where unused. The earliest mention I can find in an RFC is 1597. Also see rfc 1627. Both rfc have been obsoleted by rfc 1918

Solution 3:

I forwarded the question to the internet-history mailing list and Craig Partridge, chief scientist at BBN, said:

10.0.0.0 is easy. For folks who needed LARGE private networks the only large space available by the early 1990s was the old ARPANET network number (the ARPANET was net 10 and was decommissioned around 1991).