A good tool to measure Caching, Size of pages, Authentication and Performance is Fiddler:
· you can go to https://www.fiddler2.com to get the tool and then:
· Training: https://fiddler2.com/Fiddler/help/ - I watched the demonstration videos, which were helpful
· Fiddler PowerToy - Part 1: HTTP Debugging: https://msdn2.microsoft.com/en-us/library/bb250446.aspx
· Fiddler PowerToy - Part 2: HTTP Performance: https://msdn2.microsoft.com/en-us/library/bb250442.aspx
· see https://httpweb for some more details on the status codes