The problem is not all systems are *nix. Windows doesn&#x27;t enforce the &lt;1024 port restriction. The advantage of using port 443 I suppose is that it&#x27;s so commonly used it&#x27;ll probably (maybe) be tied up with one service or another when it comes to any important host. I guess. But really it&#x27;s all guesswork and hope when it comes to deciding how to validate host control.