Steam Port Uses

[billvasser]

Hello. I'm trying to set up Steam on my friend's computer, and I got this port list from Steam's website. I know how to configure them in the router, but I was just wondering; Does anybody know exactly what these ports do with steam?

UDP 1200
UDP 27000 to 27015 inclusive
TCP 27015 to 27039 inclusive

 

[Bullseye]

i've tried themm but I still haven't succeeded in hosting a server or anything like that..
the ports simply allow steam to gain acces to the internet.. updates and everything.. and also the hosting of games i think :dork:

 

[billvasser]

But, does it allow full access to Steam, or just access to download and update games? I'd like the capability to allow Steam access to downloading games and playing them on a LAN, but not to play games on the internet. A documentation of the uses for each of those ports is more what I'm looking for, but with the earlier goal in mind. I just want to allow Steam without internet play!

 

[cport80]

UDP 1200 is for the friends service. I suspect TCP 27015-27039 is the range used for setting up your own server. Not sure about the other UDP range tho.