Unable to read data from DLMS meter that uses dynamic ip and UDP

HI,

I am experiencing issues with reading data from a meter that pushes messages over UDP. The meter has a dynamic IP address, so I am using the connection initiated by the meter. I can receive and translate some data in the OnReceived event.

However, when I try to use the connection established by the meter using the attach method, I receive the following error:

Disconnecting from the meter.
Failed to receive reply from the device in given time.

Below is the response and the translated XML:

[2025-03-05 09:04:52] Data from client : 00 01 00 01 00 66 00 6E DB 08 41 4D 58 07 01 7D 78 43 63 30 00 00 0E BA 57 D0 0B 3E 95 C2 8A 8C B6 61 32 E7 BA BF CE EE 48 A9 D8 7A 38 09 3B DA 6D E2 EE CB AF 11 B7 2B 75 53 90 85 16 3F 29 B0 47 A7 06 13 06 E2 48 08 D8 AC 95 28 8E A9 CF EC 1F BA C2 74 51 04 A7 91 AC 26 B3 CC 4C 0C E7 72 DD B5 D3 43 45 26 A1 4B 6B 4C 2B 25 2E 16 0C 81 05 6E 0F CB C0 BA

Translated XML:

<Structure Qty="0D" >
<OctetString Value="0000190900FF" />
<OctetString Value="414D5852303732323235303030303033" />
<OctetString Value="07E90305030D050900003C00" />
<UInt32 Value="0A38FD06" />
<Enum Value="05" />
<Enum Value="09" />
<UInt32 Value="0196D766" />
<UInt32 Value="0000186E" />
<String Value="20404" />
<Int8 Value="1C" />
<Int8 Value="47" />
<Int8 Value="0D" />
<Enum Value="00" />
</Structure>

Send AARQ request

TX: 9:04:52 AM 00 01 00 66 00 01 00 3F 60 3D A1 09 06 07 60 85 74 05 08 01 03 A6 0A 04 08 41 4D 58 07 01 7D 78 43 8A 02 07 80 8B 07 60 85 74 05 08 02 00 BE 17 04 15 21 13 20 00 00 00 00 74 30 94 E9 49 7C E9 EC B1 6B 67 B7 8D 5A

TX: 9:04:57 AM 00 01 00 66 00 01 00 3F 60 3D A1 09 06 07 60 85 74 05 08 01 03 A6 0A 04 08 41 4D 58 07 01 7D 78 43 8A 02 07 80 8B 07 60 85 74 05 08 02 00 BE 17 04 15 21 13 20 00 00 00 00 74 30 94 E9 49 7C E9 EC B1 6B 67 B7 8D 5A

TX: 9:05:02 AM 00 01 00 66 00 01 00 3F 60 3D A1 09 06 07 60 85 74 05 08 01 03 A6 0A 04 08 41 4D 58 07 01 7D 78 43 8A 02 07 80 8B 07 60 85 74 05 08 02 00 BE 17 04 15 21 13 20 00 00 00 00 74 30 94 E9 49 7C E9 EC B1 6B 67 B7 8D 5A

After three attempts, the meter disconnects, and I receive the timeout error.

I am using GXDLMSSecureClient and GXDLMSReader's readAll method. The SystemTitle, BlockCipherKey, and AuthenticationKey are correct, as I can translate the XML successfully.

As I understand from a previous response, testing via GXDLMSDirector is not feasible for UDP connections.

Any insights on resolving this issue would be greatly appreciated.

Thanks,
Attila