use Net::RawIP;

my $packet = new Net::RawIP({udp=>{check => 0}});

$packet->set({
        ip => {
                saddr => "192.168.10.10",
                daddr => "192.168.10.20"
            },
        udp => {
               source => 6544,
               dest => 514,
               data => 'test123'
            }
        });

$packet->send;