> Any port below 1024 signifies that it is a "privileged port". This is an archaic distinction that developed in high-trust R&E networks, but it did signify that the listener on the port had administrative/root access to spawn a service there, so it was kind of a signal that you could "trust" the remote server with your login credentials.

If something is running on a privileged port is not enough to trust it. Firstly you need to trust to a host, you need to know where are you connecting to. If you connect to a random host with a privileged port and pass it your credentials you are doing stupid things.

This thing with privileged ports is protecting you from users who could run arbitrary code on a server. From them and not from anyone else. So for MUD there is a lot of reasons to run on 23 port, it is a signal for users of MUD that they are connecting to a process hat was started by the owner of the machine having the root.

> If your favorite MUD runs on port 23 today, such as nethack or something, then I am glad for this change, which will force the administrator to select a unique port that does not imply privilege, TELNET protocol, or shell login credentials. It is totally RFC-compliant to select an unassigned port above 1023, and MUD conventions have popularized several numbers that are still recognizable to players today.

If I was running a MUD, I would find some way to get around. I could use 22 for example, though it could cause me problems with logging in with ssh. But it is not an issue really, there are 1k privileged ports, I could choose one from them.

You have contradicted yourself within your comment. Either a "privileged port" can be trusted or it cannot.

As I implied in my previous comment, "privileged ports" are no longer a signal of trust on Internet hosts. Literally anyone could have administrator access to a host. The MUD could be running on a Raspberry Pi in a guy's basement. A telnetd server could be on port 23 of a personal router. You could telnet into a print server, a washing machine, or a microwave oven.

In a world where devices are cheap, personal, and accessible, anyone could be an administrator of anything.

You say "privileged ports ... protect you from users who could run arbitrary code" which makes no sense, man! Unprivileged users can always run arbitrary code unless they can't! Administrators must be able to run arbitrary code! Why should you be protected from that? If someone cannot run arbitrary code then chances are that they cannot bind a "privileged port" so is that what you meant?

Again, why does a MUD need a privileged port? Why? No reason. The vast majority of "privileged ports" are occupied and assigned. You do not want to use them. You have no reason to use unassigned, privileged ports for a MUD. It is not a question of "trust" or "arbitrary code" or authenticated users -- it's just a dumb game with no effects on the OS or host system, man! It's a virtual system!

I am afraid that MUD gaming has messed with people's minds more than social media. I myself was psychologically damaged by it. I urge you to seek help, before anyone else posts incoherent comments in this thread today.