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                      ;