The only URL required to be whitelisted by customers external firewalls for Data Platform is the following:
http://tus50.bdna.com/
This URL is used to access the Technopedia catalog and download and complete catalog syncs in order to update the library.
You can verify this URL in the Admin Console by going to the Technopedia page and clicking 'Catalog Settings' and checking 'Offline synchronization' - here you will see the link.