5 ms·

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

jmcqk6 13y ago
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.
- benjarrell 13y ago
  From http://tools.ietf.org/html/rfc1918 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)
- randomdata 13y ago
  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 https://tools.ietf.org/html/rfc1918#page-4
- oasisbob 13y ago
  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 13y ago
    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).
- glitch003 13y ago
  I have a 192.40.x.x address assigned to a VPS I have from a small random hosting company in colorado.
- groovylick 13y ago
  I got 3 192.x.x.x addresses from Ramnode for one of my nodes. They can't be that rare.
deleted 13y ago
[deleted]
dalore 13y ago
Well according to RFC1918 only the 192.168.x.x space is private as it's a /16.
davidw 13y ago
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 13y ago
  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.

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.

benjarrell 13y ago
From http://tools.ietf.org/html/rfc1918 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)
randomdata 13y ago
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 https://tools.ietf.org/html/rfc1918#page-4
oasisbob 13y ago
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 13y ago
  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).
glitch003 13y ago
I have a 192.40.x.x address assigned to a VPS I have from a small random hosting company in colorado.
groovylick 13y ago
I got 3 192.x.x.x addresses from Ramnode for one of my nodes. They can't be that rare.

deleted 13y ago

[deleted]

dalore 13y ago

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

davidw 13y ago

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 13y ago
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.