How to identify the downtime of a device based on the Ping Response Time report?
On the Ping Response Time report page, there is section below called 'Raw Data'. To determine the estimated time a device went down, look for the 2 ping response records that have a huge deviation. In the below example, ping is setup to run every 15 minutes, it stopped receiving ping at about 9/26/2012 9:00:00 AM and resumed on 10/2/2012 1:15:55 PM. So from this raw data, you can estimate that the device went down after 9/26/2012 9:00:00 AM. Unfortunately, the exact time the device went down cannot be determine by this. You have to look at the device logs to extract that piece of information.