The elusive topic of users being able to allocate ports has come up several times on bboard and has yet to be documented. Here's official word from smj:
TACKER: smj (Stephen M. Jones) SUBJECT: .. SDF user port allocation DATE: 20-Apr-13 22:35:45 HOST: ol Its quite simple and should be add to the tutorials. The port number is based on your numeric id. You may run a simple server process on meta.sdf.org as long as it does not circumvent a membership (for instance, running your own webserver to host your own domain name bypassing the VHOST membership). IRC bots are fine and servers of reasonable or less foot print. For instance if you ran a nickserver or bot you'll likely be fine. If you run a minecraft server you'll probably get emails from other users asking you to stop hogging CPU and Memory.
How To: Now that you know the policy, you might ask yourself, how do I get my numeric id? Which system provides the correct numeric id? Answer is simple, you run the `id` command from any cluster server, and note your uid, this is your numerically assigned port number. Example: $ id uid=56395(user) gid=500(arpa) groups=500(arpa),600(MetaARPA),900(motd) in the above example, note the port number would be 56395. You are now ready to setup your server software.