[0.13.15] My isp provider blocks nat punching

[LoSboccacc]

just if you are interested in testing the STUN code in 0.13.x, I'm stuck with a provider from hell that seems to apply weird arbitrary rules to nat punching, so that half of the games I play have a hell of trouble working unless under vpn


so, if you want to do some testing, I got this server running where everyone else but me can connect

I guess it might be related by some obscure nat traversal rules on my isp, most likely client port would have to match server port. currently server to client communication is on a random port

15:18:42.903314 IP me-ip.61102 > server-ip.34197: UDP, length 36
15:18:42.907766 IP server-ip.34197 > me-ip.61102: UDP, length 173

is there a way to have the client port match or at least user defined? so that I can start testing out the port space and see if something works.

[Fr0ns]

I don't get a few things, is the server on the same network as you (the client)? Also, what do you mean by "is there a way to have the client port match or at least user defined?". You can add a port number after the IP on direct connect.

[LoSboccacc]

no the server is a real server. I'm on a bad isp, which does funny nat. for udp, I think if the source port doesn't match the destination punching won't work

[LoSboccacc]

If you remember from the previous FFF, our map downloader was having some extremely rare problems with some mysterious packets that would always get filtered over the Internet. We already had a fix for it, but I was curious what was going on. Thanks to the investigative power of the Factorio community, we found out that all those mysterious packets, before NAT, had a checksum of 0xFFFF. Admalledd from the forum sent some hand-crafted packets through his Internet connection and surprise, all packets would go through, except those with a checksum of 0xFFFF or 0x0000. At this point I would just assume this ISP(and some other few ISPs around the world) have some faulty hardware or software that do not handle these special cases of UDP checksums.

TOLD YA

ok ok I jest but this explains a lot of the trouble I was having and should be useful info for all other games that have random troubles playing in my network

[posila]

TOLD YA

Questing is ... does it work better in 0.14.22 for you?

[LoSboccacc]

just tried, and, no

oh well.