http://www.pc-library.com/ports/tcp-udp-port/1200/ Wrote:Technical description for port 1200:
The port 1200 is used by the Steam Friends Applet. This application is used to distribute, manage and play games and other multimedia files. A client is installed on the computer. This program is used to connect to the remote server to access authorized and paid media. The port 1200 is used to stream the data to the client app.
The port 1200 is also used by the SCOL virtual reality technology. The protocol is assigned to the port for the use of SCOL 3D virtual worlds. The SCOL technology is used particularly in the Cryopolis chat community. When the user accesses a virtual world online, the request is answered by streaming data to the user_s computer via the port 1200.
The port 1200 may be used by malware programs as well. One example is the NoBackO remote access Trojan. This can enter the system via the ports 1200 and 1201.
Now, why do people insist on opening port 1200 for game servers? This port is only used for the steam client, not the server executable.
Also, I have only seen srcds.exe receive data on port 27015 TCP and UDP ( with the exception of the sourceTV port )
If somebody would like to share proof of port 1200 and it's use as an inbound port for srcds.exe. Please do tell.
If not, can we please stop telling folks to forward / open it.
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