5 hours ago, MrFuzzy said:

How do you explain the benefits experienced by various users?

Also, when "Teredo is unable to qualify" there is no real time traffic, I can encounter 1-2 aircraft in normally crowded areas, whereas with "NAT Open" the ATC is very active and I even get frequent traffic alerts for aircraft near me.

It’s just random. I’ve noticed sometimes switching to a different server and back kicks it in the butt.

Some days I can go from NYC to Miami and only few a few planes, sometimes I’ll run into dozens.

It’s just how the servers are feeling that day.

Edited June 1, 20215 yr by Tuskin38

4 hours ago, MrFuzzy said:

How do you explain the benefits experienced by various users?

Also, when "Teredo is unable to qualify" there is no real time traffic, I can encounter 1-2 aircraft in normally crowded areas, whereas with "NAT Open" the ATC is very active and I even get frequent traffic alerts for aircraft near me.

Pressing the “fix problems” button in the X-Box networking app does more than just check whether Teredo is active. It may be fixing something else. Since Teredo is disabled by default in Win10, the “Teredo is unable to qualify” message is a perfectly normal and expected result when doing a network check with the X-Box app.

As I explained, Teredo is only concerned with IPV6 packets. It is a “last resort” way to use IPV6 if there is no other way to do it. I have never seen MSFS make an IPV6 connection. I use a program called CurrPorts which will monitor all TCP/IP connects made by all running processes on a Windows computer. Every network connection MSFS makes is IPV4.

Teredo is fully disabled on my machine, and though I normally run both IPV4 and IPV6 on my network card, if I turn IPV6 off, all MSFS features work fine, including live weather and live traffic.

Even if a particular game does require IPV6, Teredo is absolutely the last way one would want to achieve that. Direct IPV6 is far superior. Terrdo was created at a time when native IPV6 was less commonly supported by network cards, routers and ISPs - that is no longer the case in 2021, which is why Teredo is disabled by default on all new Win 10 installations. Microsoft absolutely does not want users to routinely use Teredo. They have been trying to sunset Teredo for years, and they could finally shut down their Teredo servers at any time. They initially proposed doing so as far back as 2014.

If an MSFS networking feature is not working, it is far more likely that the root cause is that the Windows firewall is not allowing a required TCP/IP port to be opened. When the firewall blocks a connection it should pop up a message to that effect, but I know from experience that is not always the case. This can also be affected by some aftermarket Antivirus packages that may use a custom firewall to supplement or replace the default firewall.

Since MSFS does not use IPV6, and Teredo deals exclusively with IPV6 connections, Teredo itself cannot possibly be the reason why some feature starts working after users go through the process of turning it on.