function GetAdapterInfo(Lana: Char): String;

var

Adapter: TAdapterStatus;

NCB: TNCB;

begin

FillChar(NCB, SizeOf(NCB), 0);

NCB.ncb_command := Char(NCBRESET);

NCB.ncb_lana_num := Lana;

if Netbios(@NCB) <> Char(NRC_GOODRET) then

begin

 Result := 'mac not found';

 Exit;

end;

FillChar(NCB, SizeOf(NCB), 0);

NCB.ncb_command := Char(NCBASTAT);

NCB.ncb_lana_num := Lana;

NCB.ncb_callname := '*';

FillChar(Adapter, SizeOf(Adapter), 0);

NCB.ncb_buffer := @Adapter;

NCB.ncb_length := SizeOf(Adapter);

if Netbios(@NCB) <> Char(NRC_GOODRET) then

begin

 Result := 'mac not found';

 Exit;

end;

Result :=

 IntToHex(Byte(Adapter.adapter_address[0]), 2) + '-' +

 IntToHex(Byte(Adapter.adapter_address[1]), 2) + '-' +

 IntToHex(Byte(Adapter.adapter_address[2]), 2) + '-' +

 IntToHex(Byte(Adapter.adapter_address[3]), 2) + '-' +

 IntToHex(Byte(Adapter.adapter_address[4]), 2) + '-' +

 IntToHex(Byte(Adapter.adapter_address[5]), 2);

end;

function GetMACAddress: string;

var

AdapterList: TLanaEnum;

NCB: TNCB;

begin

FillChar(NCB, SizeOf(NCB), 0);

NCB.ncb_command := Char(NCBENUM);

NCB.ncb_buffer := @AdapterList;

NCB.ncb_length := SizeOf(AdapterList);

Netbios(@NCB);

if Byte(AdapterList.length) > 0 then

 Result := GetAdapterInfo(AdapterList.lana[0])

else

 Result := 'mac not found';

end;

function GetMACAdress: string;
var
  NCB: PNCB;
  Adapter: PAdapterStatus;

  URetCode: PChar;
  RetCode: char;
  I: integer;
  Lenum: PlanaEnum;
  _SystemID: string;
  TMPSTR: string;
begin
  Result    := '';
  _SystemID := '';
  Getmem(NCB, SizeOf(TNCB));
  Fillchar(NCB^, SizeOf(TNCB), 0);

  Getmem(Lenum, SizeOf(TLanaEnum));
  Fillchar(Lenum^, SizeOf(TLanaEnum), 0);

  Getmem(Adapter, SizeOf(TAdapterStatus));
  Fillchar(Adapter^, SizeOf(TAdapterStatus), 0);

  Lenum.Length    := chr(0);
  NCB.ncb_command := chr(NCBENUM);
  NCB.ncb_buffer  := Pointer(Lenum);
  NCB.ncb_length  := SizeOf(Lenum);
  RetCode         := Netbios(NCB);

  i := 0;
  repeat
    Fillchar(NCB^, SizeOf(TNCB), 0);
    Ncb.ncb_command  := chr(NCBRESET);
    Ncb.ncb_lana_num := lenum.lana[I];
    RetCode          := Netbios(Ncb);

    Fillchar(NCB^, SizeOf(TNCB), 0);
    Ncb.ncb_command  := chr(NCBASTAT);
    Ncb.ncb_lana_num := lenum.lana[I];
    // Must be 16
   Ncb.ncb_callname := '*               ';

    Ncb.ncb_buffer := Pointer(Adapter);

    Ncb.ncb_length := SizeOf(TAdapterStatus);
    RetCode        := Netbios(Ncb);
    //---- calc _systemId from mac-address[2-5] XOR mac-address[1]...
   if (RetCode = chr(0)) or (RetCode = chr(6)) then
    begin
      _SystemId := IntToHex(Ord(Adapter.adapter_address[0]), 2) + '-' +
        IntToHex(Ord(Adapter.adapter_address[1]), 2) + '-' +
        IntToHex(Ord(Adapter.adapter_address[2]), 2) + '-' +
        IntToHex(Ord(Adapter.adapter_address[3]), 2) + '-' +
        IntToHex(Ord(Adapter.adapter_address[4]), 2) + '-' +
        IntToHex(Ord(Adapter.adapter_address[5]), 2);
    end;
    Inc(i);
  until (I >= Ord(Lenum.Length)) or (_SystemID <> '00-00-00-00-00-00');
  FreeMem(NCB);
  FreeMem(Adapter);
  FreeMem(Lenum);
  GetMacAdress := _SystemID;
end

Добавляешь имя NetBIOS и посылаешь на имя станции, нужной для опpеделения(можно
и своей) датагpамный пакет с заполненным NCB.