Internet video UDP-range - STUN?

[ChrisCon]

Our HR uses Interview from Indeed https://interviews.indeed.com/demo/video/
I've tried to open firewall ports with application STUN, service ANY.
But that did not work (error message because of missing "network connection").
For testing I've opened all ports for my user, that worked. So I knew it's the firewall.
I've ended up with trial and error.
At the end I added new service with UDP-ports 3478, 12000-20000 and made firewall policy with this service.
This seems to work, at least most of the time.
Maybe there is a more elegant way?
Thanks.

[BPry · Accepted solution]

@ChrisCon,

Have you checked your traffic logs after creating your test allow any rule or enabled logging on your interzone-default entry? Indeed uses Twilio on the backend for their video interview process, so I would be validating that you aren't blocking anything being identified under the Twilio app-id. 

Twilio themselves also published all of their required communication HERE that would at the very least allow you to lock this down to actual required hosts if you aren't already doing so. 

[ChrisCon]

Thanks for the hint with Twilio.