Encoders use HTTP to connect to a server running Windows Media Services. By default, Windows Media Encoder uses port 8080 for HTTP connections; however, the encoder administrator can specify a different port. If a different port is used, you must specify the same port when you identify the encoder connection URL for the Windows Media server and when opening the port on your firewall.
The following example firewall configuration allows a computer running Windows Media Encoder outside of a firewall to access a Windows Media server behind a firewall by using HTTP. The In port is the port through which the server accepts connections. The Out port is the port through which the server sends data to clients:
In/Out: TCP on port 8080.