Why would I be getting "LEN 1 (Malformed Packet)"... "(Malformed Packet: RTCP)" on UDP Packets

asked 2017-11-14 16:40:30 +0000

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We are communicating across separate VLANS with a Router in between, and can access field switches and successfully ping all field devices. The system manufacturer notes that they are seeing UDP traffic sent out by the system server, but that the server isn't receiving responses. I ran captures in Wireshark with the following results. Any idea why UDP packets would be reported as "Malformed" ... "Malformed Packet: RTCP"?

Any help would be appreciated. Capture included.

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Have you sliced the frames during capture?

Christian_R gravatar imageChristian_R ( 2017-11-14 16:47:21 +0000 )edit

Can you share us a trace?

Here is a tutorial how you can share pcaps at Wireshark Q&A: https://blog.packet-foo.com/2016/11/t... the trace file is not so big you can attach it directly here, if you press the "attach a file" button at the answer field

Christian_R gravatar imageChristian_R ( 2017-11-14 19:14:03 +0000 )edit

Also check your preferences. Is there an UDP port configured for the RTCP protocol?

Jaap gravatar imageJaap ( 2017-11-14 20:42:30 +0000 )edit