Connecting your computer to a network isn’t hard, but plenty of stuff goes on behind the scenes to make it work. One part of that is ports: channels that carry a certain type of traffic. The multi-user version of our new accounting software needs one so clients and servers can talk to each other, whether over a LAN (local area network) or an Internet connection.
There are 65,535 possible ports (two bytes minus one). First up are the well known ports, using the first 1,023 numbers. For example, http web traffic moves over port #80, while encrypted https uses #443. For email, there’s #109 for POP2 and #110 for POP3.
Most well-known ports are already allocated for something. They are much too classy for our accounting software.
Next step up are the registered ports, from 1,024 to 49,151. Only 10% of those are filled. Last week TurtleSoft sent in an application to register #21,587 for the new app. It’s TS as text. Goldenseal has been using #18,259, which translates to GS, but we want to keep them separate.
The Internet Assigned Numbers Authority (IANA) assigns ports. Sadly, they shot us down, and said to use the temporary range (49,152–65,535) instead. We appealed, explaining how users needed something easy to remember. Nope, shot down again.
Then we looked at the list of registered port numbers on Wikipedia. TurtleSoft is not the only one out in the cold. Apple, IBM, Microsoft, Cisco, Minecraft and many others use an unofficial port number rather than a registered one. Apparently IANA is stingy to everyone.
Right now, nobody else has registered GS or TS, and that status probably won’t change. So we will use 21,587 (TS) unofficially for the new multi-user accounting software. In the unlikely case that our port conflicts with some other app, you can easily switch to a different number.
Meanwhile, the networking code is almost finished. Soon we can get back to regular testing and programming.
Dennis Kolva
Programming Director
TurtleSoft.com
