MATLAB not receiving packets

Hi All,

I have some hardware that is continuously outputting packets to a multicast address. I have setup a MATLAB script that should receive the packets and store them. I have this working on an older version of Windows, so I'm pretty confident the code is working but since we upgraded our systems, the code is no longer working. This could be due to the group policy of the PCs but any troubleshooting ideas would be very helpful. I can see the incoming packets in Wireshark going to the correct address and port and I am setup via a direct connection. The network adapter used has also been set to have the highest priority. MATLAB is also successful at sending packets out to my hardware, just not receiving them.

udpport("datagram","LocalHost",'X.X.X.X',"LocalPort", X, "EnablePortSharing", true);
configureMulticast(DiscoveryListeningPort, "X");
DiscoveryListeningPort.OutputDatagramSize = 30;

When checking my defined udpport I can see 'NumAvailbaleDatagrams' 0. This is making me more confident that the packets aren't reaching MATLAB. Are there any ways to resolve this?

Answer 1

[Vidip]

The packets can be rejected due to the MAC address mismatch between the remote device and address of your ethernet adapter. Apart from this, write a simple UDP multicast receiver in another programming language (such as Python) or use a network utility tool to test whether the system can receive multicast packets outside of MATLAB. This can help determine if the issue is specific to MATLAB or the system itself.

Also, check if your firewall settings are allowing incoming UDP packets on the port you're listening to. Firewalls can block incoming traffic, which would prevent MATLAB from receiving the packets.

For further information, refer to the documentation link below:

• https://in.mathworks.com/help/instrument/troubleshooting-udp-interface.html