Writing a report that records downtime due to power outages.

I am not an SQL guru for that matter thus am in dire need of your help in writing a report that can enable me monitor a network and report on the times when this network goes down, not because the ISP is not doing its job, but rather when the router at that site goes down due to a power outage. We should Also consider the fact that this monitoring is only relevant during working hours, i.e. 8 AM - 8 PM. Thus this report should put that into consideration. My biggest challenge came when trying to determine the attribute on the router/node that I should monitor to enable me record events that are bought about my power outages on the router. Thank you