Is it normal that the Windows is sending a lot of junk packets into the Wireguard network interface?
I checked with Wireshark and I was seeing NetBIOS, LLMR, LDP etc. IGMPv6 etc. packets being sent into the tunnel.
Not sure any of these have privacy implications but I don't think they should be sent into the tunnel, they don't really make sense when the interface is really just Point to Point.
I did the two following things manually which actually stopped all the weird/junk traffic:
1. disable all superfluous Microsoft "items" on the tunnel interface
"Client for Microsoft Networks" -> local broadcast discovery packets (?), there are no devices to discover
"File and Printer Sharing" -> obviously useless junk, there are no printers in the tunnel link-local network
LLDP-related options -> probably pointless in a point-to-point interface too
2. explicitly disable NetBIOS on the interface (from Administrator prompt)
wmic nicconfig get caption,index,tcpipnetbiosoptions
wmic nicconfig where index=<WireGuard NIC index> call settcpipnetbios 2
However, because this interface is ephemeral, changes do not stick
Could these settings be performed by Eddie or WireGuard-NT in some automated way when creating the tunnel interface, at least optionally? Otherwise the only option is to go back to using the WinTun userspace version again (which does not seem possible in "Preferences"), or to OpenVPN, because those interfaces are not recreated on every reconnect.
In general, I see no reason not to disable all of these "extra" things that Windows sends into the tunnel by default. Maybe NetBIOS could stay as something that can be disabled optionally (though I think 99% of windows users don't need NetBIOS on their Internet-facing adapter in any case).
These current settings allow lot of junk packet traffic (5-10 packets per second), but it might also be concerning from a privacy point of view (though I don't know enough about these protocols to say for sure).
Also, on a laptop, it doesn't seem good for battery life that all these junk packets are constantly saturating the wireguard interface (they keep WiFi/5G awake).