RUM vs. Synthetic Testing
Synthetic testing, also known as synthetic monitoring, uses browser emulation to simulate an end user’s interaction with your Web site. Synthetic tests emulate the common paths end users would follow when visiting your Web site.
While synthetic testing simulates users, and is repeatable and often reliable, it does not provide data on actual end-user experiences. As RUM measures performance directly, you can use the available filters (like country and browser) to drill down into your RUM data and see what subset of end users are experiencing problems.
As you collect and analyze your RUM data, you may notice trends that may cause you to alter your synthetic tests to better reflect your customers’ experience with your site.