What is required for a RSS feed to display

I have a 1.7.4 server and most of my clients are either 1.7.3 through 1.7.5. If I want to display a RSS feed from a site outside the Intranet, from News24.com or the BBC for instance and both the server and the clients are sitting behind the firewall, do either the clients or the server have to have access through the firewall to the Internet RSS, or both…?

CMS will need access, then content (items from the feed in this case) should be then sent from CMS to clients.