Disclaimer: Advice is provided to the best of my knowledge but no implicit or explicit warranties are provided. Since the advisor explicitly encourages testing any and all suggestions on a test non-production environment advisor should not held liable or responsible for any actions taken based on the given advice.
Support PAVB. Just to add, you can do it in several ways. I believe you can make the listener filter the connections, or use connection manager.
PAVB's proposal however seems to be simple, easy and reliable.