Originally Posted by qwertyjjj
I've been looking up CIDR but can't really get an explanation on anything that isn't 8bit, 24, etc.
I currently use this rule in a .htaccess file to restrict logins to the admin pages from my ISPs range:
Deny from all
Allow from 18.104.22.168/11
It works but my IP address is 81.159.xxx.xxx
I'm not really sure how the 11 factors into the equation?
I was going to use the same in iptables
there is a short but sweet explanation on wiki
loads of detailed explanations too on the web. i didnt really understand it properly until i did the ccna.. so you may have to read up some good books for a 'proper' understanding
even shorter and sweeter is the iptab command or ipcalc which will work it all out for you if you give the relevant flags