On Mon, Feb 07, 2005 at 02:08:54PM -0500, warrier@xxxxxxxxxxx wrote: [.. addresses in 127/8..] > Do you have any idea how this is implemented in Linux? , which > source files I should look at etc. Not really. Look around in /usr/src/linux-version/net/ipv4/ Anyway, I suggest you just stick to private addresses; 256 /24 nets; 192.168.x.x 16 /16 nets; 172.16.x.x through 172.31.x.x 1 /8 net; 10.x.x.x These nets will never be routed on the internet. Also you seemed to have net length meaning confused; /24 is 255.255.255.0 /16 is 255.255.0.0 /8 is 255.0.0.0 /n means netmask with n number of ones. //Peter