When the Open Agent starts, a random available port is assigned to Silk Test Classic and to the application that you are testing. The port numbers are registered on the Silk Test information service (information service).
By default, the Open Agent communicates with the information service on port 22901. You can configure additional ports for the information service as alternate ports that work when the default port is not available. By default, the information service uses ports 2966, 11998, and 11999 as alternate ports.
Typically, you do not have to configure port numbers manually. However, if you want to test on a remote machine and there is a port number conflict or an issue with a firewall between the machine on which Silk Test Classic is installed and the test machine, you can configure the port number for the communication between Silk Test Classic and the Open Agent on the remote machine or the port number for the communication between Silk Test Classic and the information service on the remote machine. If you have multiple remote machines on which you want to test, you can use different port numbers for each remote machine or you can use the same available port numbers for all remote machines.
The following image shows the communication between Silk Test Classic, the information service and the Open Agent.