On UNIX like operating systems, an IP address can be sorted using the utility sort, part of the GNU Core utils
sort -n -t . -k 1,1 -k 2,2 -k 3,3 -k 4,4
-n, –numeric-sort compare according to string numerical value
-t, –field-separator=SEP use SEP instead of non-blank to blank transition
-k, –key=POS1[,POS2] start a key at POS1 (origin 1), end it at POS2
If you like a well written explanation of this, I invite you to read this article by Paul Heinlein.