[Galene] Interferences with Zoom or other VC software

[Galene] Interferences with Zoom or other VC software

[Michael Ströder]

HI!

Disclaimer: This is likely at least partially off-topic. But maybe it's
an interesting interop issue relevant for this community.

I generally recommend users to switch off all other video-conferencing
apps when connecting to my Galène instance. Because often mics and
cameras are blocked etc. But hey, users don't care much of what I write.

One user had serious connection problems today, we couldn't solve, and
thus I've searched through the logs.

What I found strange was the IP address 198.251.148.185 connecting to
the classic STUN port 3478. This port is not mentioned in Galène's
ice-servers.json. Well, could be the usual script kiddy.

But the really strange thing is that this seems to be a Zoom address:

$ whois 198.251.148.185
NetRange:       198.251.128.0 - 198.251.255.255
CIDR:           198.251.128.0/17
NetName:        ZVC
NetHandle:      NET-198-251-128-0-1
Parent:         NET198 (NET-198-0-0-0-0)
NetType:        Direct Allocation
OriginAS:
Organization:   Zoom Video Communications, Inc (ZVC)

We don't have a Zoom client installed. And our own browsers were
definitely not participating in any Zoom-related sessions.

Any idea what's going on?
Are they simply scanning the whole Internet for STUN servers?
Or are they tracking other video-conference apps on the client of the
remote user?

Ciao, Michael.