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ISP (Telekom Germany) is blocking Zoom?



I've since ~2 weeks the issue that my router (speedport smart 3) firewall (which can't be deactivated) is blocking the IPs from Oracle cloud which is used for zoom calls. 

In the logs I can see that entry: 
Firewall event: An event [UDP SYN FLOOD IP] : was detected. Address 193.122.*.* : 8801 was identified as the sender. The recipient was identified as 84.173.*.* : 63827.

* were added by me to hide the full ip adress. 

Telekom is not aware of any issues and asked me to reach out to zoom if they are any settings which might create these issue.


Community Champion



Sorry for the delay in responding.  Based on articles I have found, the problem is with the mesh WiFi on the Speedport Smart 3 router.  (Based on the error, it apparently thinks it is a denial of service attack).  Apparently, version 4.8.0 of the Speedport firmware fixes this issue.


I hope you have already resolved this, but if not, please try to upgrade the firmware.