[oasisbob]

Similar: not every 192.x.x.x IP address is in a private (RFC1918) network.

[dalore]

Well according to RFC1918 only the 192.168.x.x space is private as it's a /16.

[jmcqk6]

This is interesting. Do you know who controls these public addresses? I know in the past I've seen filtered connections to 192.x.x.x thinking that it would get only internal connections then. The owners of these public addresses could wreak havoc in some places.

[randomdata]

RFC1918[1] defines 192.168.x.x as the private address space, so anything else in the 192.x.x.x range would not fall under that specification.

[1] https://tools.ietf.org/html/rfc1918#page-4

[benjarrell]

From http://tools.ietf.org/html/rfc1918

The Internet Assigned Numbers Authority (IANA) has reserved the following three blocks of the IP address space for private internets:

     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)

[oasisbob]

There's a university with a 192.16x.x.x allocation who has written about the confusion it's caused.

Nothing that special about it from a CIDR point of view -- but is rather confusing to us humans when written as a dotted quad.

Github's GITHUB-NET4-1 is on 192.30.252.0/22, which is what reminded me of this.

[cbhl]

Heck, the University of Waterloo has 129.97.0.0/16, and I see people get confused all the time between 192.168. (private) and 129. (publicly routed).

[groovylick]

I got 3 192.x.x.x addresses from Ramnode for one of my nodes. They can't be that rare.

[glitch003]

I have a 192.40.x.x address assigned to a VPS I have from a small random hosting company in colorado.

[davidw]

I always wonder why people don't just use 10.0.0.X - it's easier to write, to tell people on the phone, and to remember if needs be.

[rogerbinns]

Several reasons. The biggest is what netmask to use. 192.168.x.x was originally a class C (/24) and the default netmask to use is that resulting in the least number of problems.

With 10.x.x.x, the original was class A (/8) but it is extremely unlikely you want that as the netmask. Other guesses could be wrong.

Additionally because of its size, it is likely used in corporate networks. This would cause grief with vpns if both your local network is 10.x.x.x and the corporate vpn is 10.x.x.x.