It is possible to select Match Viewer, HTTP, or HTTPS as the standard protocol for requests from CDNs to the origin server. The main difference is whether the connection is secured by an SSL certificate or not.
Unless you have special requirements that exclusively need HTTP as the standard protocol, we strongly recommend using HTTPS or Match Viewer to establish a secured connection to avoid various types of attack such as Man-in-the-Middle Attack.
Unlike HTTP and HTTPS, Match Viewer allows you to swap between HTTP and HTTPS port freely instead of committing to just one.
You can configure this at the following locations:
When adding a site - You can set this when adding a site
After a site is added - Click the settings icon on the site you wish to configure > Click ‘Config’ in the ‘Origin Info’ section > Select an option for ‘Origin Protocol’