It doesn't check for range, so you can do: 
use Data::Validate::IP qw(is_ipv4);

my $ip_w_mask = '10.3.2.0/28';

my ($ip, $mask) = m{^(.*)/(\d+)$}
   or die("Incorrect format: Mask not found\n");

is_ipv4($ip)
   or die("Incorrect format: Malformed IP address\n");

[download]

In reply to Re^2: Script to input IP Address and Subnet Bits (10.3.2.0/28) by ikegami
in thread Script to input IP Address and Subnet Bits (10.3.2.0/28) by jesuashok

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