NCSI - Network Connectivity Status Indicator Operation
In this video I demonstrate how Windows OS determines if it has an internet connection or not. This controls the little icon at the bottom right of the screen known as the NCSI. With a DNS name resolution and a returned text message from a Microsoft server, it shows there is at least connectivity to the internet. It doesn't address any app issues that use the web but aren't behaving, or speed or drop out issues, just basic connection.
I perform a manual DNS lookup
"nslookup dns.msftncsi.com"
It should resolve to 131.107.255.255
Then a Windows Power Shell text request to the MS server. It should return a text message of "Microsoft NCSI".
Then I use a web browser, to do both the DNS and text request at the same time.
http://www.msftncsi.com/ncsi.text