The university where I study has an IP range from 18.104.22.168 to 22.214.171.124
I'm going to find out all the domain names for every IP address, and is the IP hosts a web site (online).
Mostly they are like these:
pc-100.dormitory-5.dormitories.name_of_the_university.edu for 144.122.x.100
pc-101.dormitory-5.dormitories.name_of_the_university.edu for 144.122.x.101
I'll do it with PHP from my own computer.
The question is; how does "IP to domain name" thing works? Could it be interpreted as IP scanner? The university lists and blocks IP addresses of infected PCs (students' PSs), thus I don't want to be blocked for that reason.
I use OpenDNS.
The PHP function is
My aim is to work on arrays on PHP and I wanted to see all the networks out there in the campus, like how many dormitories are there.