whitelist it where? Are you inquiring about inbound or outbound communication?
Are you running into an issue now?
If you have any form of IP restrictions in your firewall or proxy, then, yes, you will need to whitelist the IICS Server IPs or the Informatica domains.
You can find the details for the same in the following link:
If the previous response answers your query, then kindly mark the correct answer and close the thread.
Thanks and Regards,