you could perhaps format the input in a first time and stock in your database the IP address in hexadecimal format (?)

#!/usr/bin/perl 

use strict;
use warnings;
use Regexp::Common qw /net/;
use IO::Prompt;

my $ip;

# formatting the input

while ( $ip = prompt "Enter a valid IP address: ", -until => qr/^$RE{n
+et}{IPv4}{-sep=> '.'}$/ )  {
    print "Your say: '$_'\n";
}

# dotted-quad format to hexadecimal
my $hex_ip = unpack "H*", pack "C4", split '\.', $ip;
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HTH,
PooLpi
ps : sorry for my poor english !