Why my ip address starts with 192.?

Question

i am from non networking background. I suddenly wondered why the companies i worked almost always had the ip's like 192.168.x.x . Why can't they have something like 1.2.3.4

I understand that ip has and there is a concept called subneting.

Also, 192.168.0.0 to 192.168.255.255 seems to used for private use.

Question:

1) How does IP address matters thought all devices are connected to internet through roughter?

Any wisdom pls?

Solution

According to RFC 1918, addresses in the 192.168.0.0-192.168.255.255 range are private. Such addresses can be used internally by any network so they're often used inside an organization. They cannot be used on the Internet since they aren't unique.

192.168.X.X isn't the only private range defined in the RFC. You might also run into 10.0.0.0 - 10.255.255.255 or 172.16.0.0 - 172.31.255.255

Most other addresses are public, and have to be assigned to the network by a Regional Internet Registrty (RIR).

Comments

[DrunkenMaster]

Thanks for the comment Malt. I glanced over RFC1918, and realized below statement: 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). Shall i consider apart from these ranges can not be assigned to private? for example : 9.x.x.x ?

[Malt]

Addresses outside these ranges are not private, but might be reserved for other reasons.Wikipedia has a nice list: en.wikipedia.org/wiki/Reserved_IP_addresses