Zoom Meeting issue

[Edmond]

Using FG-201E and 2 wan link for Internet.  I have a problem on using zoom meeting. If a lot of user join a same session meeting, the quality is poor. Most likely reach above 50 users. 

Any best practice guide / tuning recommendation?

Thanks.

[pciurea]

Hello Edmond its nice to have you in this community.

Are you using SDWAN to load balance traffic between the two links? (https://docs.fortinet.com/document/fortigate/6.2.10/cookbook/19246/sd-wan)

Zoom has the following bandwidth requirements:

https://onlinezoomappdownload.com/zoom-bandwidth-requirements-and-participant-bandwidth-limits/

Those values does not seem much, but they add up the more users are using the application.

I would keep an eye out for bandwidth exhaustion.

If you are not using SDWAN yet, I would advise to implement it and use the application steering - https://docs.fortinet.com/document/fortigate/7.0.2/administration-guide/125874/application-steering-...

Cheers 

[Edmond]

We are using policy route to separate the traffic in Internet link. As my observation both of WAN link usage is not really high. Session is also same as normal. 

Don't know what is the bottleneck. 

[Toshi_Esumi]

Are those 50 users at the same location behind the FGT? When I was troubleshooting Zoom related problem last time, I noticed most of UDP packets directly communicates between client devices. Don't go to the cloud. So if they're on the same LAN, those don't even come to the GW FGT. I would look at LAN bottleneck if that's the case.

[Edmond]

Thanks for your information. All those run on same network. Currently, local LAN connect to gigabit switch and with 10G backbones. I check out the zoom bandwidth requirement is not high.

How you troubleshoot last time?

[Toshi_Esumi]

The issue I was looking at last time was screen share sometimes didn't start right away. So I assumed some packet losses somewhere. I ran packet capture at a presenter and perticipant machine then run it at the local FGT. But those losses and retransmissions didn't seem to be caused by the local FGT. The location's internet goes over a VPN to get to another FGT on the other end of the tunnel. So I was looking at packet capture at the other FGT to capture the moment.

Since I couldn't get enough information from Zoom support, I really couldn't find it out before the symptom suddenly stopped happening. That peer-to-peer direct video or screen data exchange was discovered during the process in those PCAPs.

[Edmond]

After getting the tips, I monitor the traffic route and packet size. Today I have a call, 2 Presenter and participant 100. I trial a zoom webinar instead of meeting. Really strange,  presentation quality is good, but sound is sometime bad in local same network user. However, present and sound is good run as wifi (different subnet) whatever mobile or notebook  in same site same wan link. 

Also, monitor the WAN traffic going to same zoom server. Local wired PC is around 400-500B packet, Wireless notebook/mobile is around 40-80Mb per session during 1 hour. Most user are run on wired PC, only around 10 client wireless. Likely you said that peer-to-peer data exchange at LAN environment. 

[pseixas]

Do you have policy DoS enable ?! I already had the problems because policy DoS.

[Edmond]

no DoS policy enable