Why is RTP traffic from video encoders not getting captured?

asked 2022-02-16 17:21:35 +0000

pj5739 gravatar image


I have a series of IP9610E encoders and am trying to troubleshoot an issue and using Wireshark to see if I can eliminate the network or at least see what the traffic from the encoders is doing. The encoders are plugged into a Dell 3048 switch. They use RTP in a unicast connection to their respective decoders and have Fujitsu's FEC/ARQ enabled. I mirrored one of the ports from the encoder and plugged my computer into it. Wireshark is set to promiscuous mode and RTP capture enabled. I started the capture and immediately began capturing packets from all sorts of things on that VLAN, but none of the encoders' IP addresses showed up. ICMP traffic showed up however, when I pinged the encoders, but the video traffic didn't show up at all. Any idea why this is the case?

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You said you have RTP capture enabled. What happens if you try open capture? If you see the video traffic, then you will need to tell Wireshark that the UDP port is RTP.

BigFatCat gravatar imageBigFatCat ( 2022-02-16 18:00:17 +0000 )edit

Could you clarify open capture? Is that non-promiscuous mode?

pj5739 gravatar imagepj5739 ( 2022-02-16 19:07:48 +0000 )edit

Update: I tried capturing with promiscuous mode turned off and that really didn't change anything. What I to do was turn off the FEC/ARQ on the Fujitsu and also change its connection from Unicast to Unicast Simplex and then I was able to see the MPEG TS traffic.

pj5739 gravatar imagepj5739 ( 2022-02-17 18:49:40 +0000 )edit