Fighting Robots on my Firewall

Just this past weekend, my son got me back into the game we call Fighting Robots. Others know it as Total Annihilation or just TA for short.

This game is still fantastic. At first we installed the basic disk, and had to play each other. My son was not happy when I beat him. But eventually he understood. Then after we loaded the other disks, and the patch, we were able to play against computer opponents. That was a lot more fun.

Today, I was checking out my laptop. I was looking at the services. I turned on the telnet server. But I couldn't connect. Which is the correct action, as I have the firewall software turned on in XP for ethernet. So I went to allow telnet connections inbound on my compter on the firewall settings. But I noticed something odd: a service called dplaysvr at the top of the list, allowed in. What was this? Where did it come from?
My first few searches on the internet gave me some worry - some virus programs will install under the name dplaysvr.exe. But then I found some other pages talking about gaming. And I suddenly realized that it could be related to TA!
Some more searching found that it is related to DirectPlay7, which is part of DirectX. I find it very interesting that TA, which was written way before XP, was able to self-install the play service on my firewall. I can only assume that it is really because of DirectX9 being smart enough to know it needs to open the port on the XP firewall to allow TA - or any other DirectPlay game to have access.

The setting in the firewall shows:
[x] dplaysvr (255.255.255.255:47624) 47624 UDP
which matches the settings documented by microsoft in 240429 - DirectX: Ports Required to Play on a Network