Comment by sempron64

Modems were pretty sweet.

With a modem, we were able to make 1:1 direct serial connections to any other modem in the world that was connected to the Public Service Telephone Network (although for things like gaming, it was usually only local because long distance calls were expensive).

A ton of games didn't even use things like TCP/IP. They'd instead use their own simple serial protocols that were designed without the constraint of handling the whole universe of things that TCP/IP needed to be able to sort.

Just plan and set it up during a plain-old voice phone call, hang up the phone, and then have one modem call the other.

Or: If both parties were feeling adventurous, then an existing voice phone call could be turned into a data call with one end commanding their modem with ATX3D (initiate a call without waiting for a dialtone, to a <null> phone number) and the other issuing ATA (just answer) at about the same time. (This latter method avoided having the phones in the house ring unnecessarily for one party or the other, which kept peoples' parents or wives from waking up in the middle of the night and becoming grumpy.)

Modems were functionally-simple devices that certainly had their limitations, but there was a certain grace in the simplicity of using them.

And they were an excellent fit for the world at that time, wherein: Approximately every home that had a computer was also a home that had a POTS phone line.

(In a way, we had better direct connectivity back then than we do today with the CGNAT-encumbered pocket supercomputers that have broadly replaced POTS.)

Glad you mentioned DOOM! Sometimes people forget that DOOM supported multiplayer as early as December 1993, via a serial line and February 1994 for IPX networking. 4 player games on a LAN in 1994! On release, TCP/IP wasn't supported at all, but as the Internet took off, that was solved as well. I remember testing an early-ish version of the 3rd party iDOOM TCP setup driver from my dorm room (10 base T connection) when I was supposed to be in class, and it was a true game changer.

You can kinda solve that problem with STUN servers. Most games on Steam use Steam Datagram Relay, which also solves this: https://partner.steamgames.com/doc/features/multiplayer/stea...

It's like in-engine Hamachi. Works really well with P2P games.

I wonder if there is a way to use tailscale to make it easy again?

You usually just need to forward a port or two on your router. That gets through the NAT because you specify which destination IP to forward it to. You also need to open that port in your Windows firewall in most cases.

Some configuration, but you don't have to update the port forwarding as often as you would expect.

The reason you can't just play games with your friends anymore is that game companies make way too much money from skins and do not want you to be able to run a version of the server that does not check whether you paid your real money for those skins. Weirdly, despite literally inventing loot boxes, Valve does not suffer from this sometimes. TF2 had a robust custom server community that had dummied out checks so you could wear and use whatever you want. Similar to how Minecraft still allows you to turn off authentication so you can play with friends who have a pirate copy.