foreach my $port_address_table (@port_address_table) {
    foreach my $mac_address (@mac_address_result) {
        if ($mac_address eq $port_address_table){
            if ($mac_address =~/[a-fA-F1-9]$/){
                open(DATEI,">>d:/mac/mac_tabel.txt");
                print DATEI "$mac_address\n";
                close DATEI;
                push (@mac_tabel_result, $mac_address);
                %mac_ip=(
                  $mac_address => $ipaddress,
                        );