In WebSphere, there is a NODE_MULTICAST_DISCOVERY_ADDRESS port that goes to a static IP address that you have to define in your network.
This is not required for an application to run, but you cannot disable it.
It tries to make an outbound call every minute and shows in the CSP logs. When troubleshooting real connection issues, this makes it very difficult to find the problem.
I recommend that you allow a ignore list feature that allows you to prevent logging of blocked ports in the logs to make it easier to track down real issues.