Thanks for this solution!
In my case however I cannot reach my home from the web due to being behind multiple NATs. So I took your solution and added to it a little.
Since the ISY doesn't have the ability to ping, I wrote some REST services for my windows server at the house. When the /Services/REST/isy/iNetCheck is called on the server, it pings Google. If the pings are successful the REST service on my server then calls the REST service on the ISY to set the i.InternetTest variable to 1.
Doubt this would work for everyone but let me know and I'll share the project. It's a C# ASP.Net project. It also requires that the PC be running 24/7. That however isn't an issue for me since my server never shuts off due to RAID, PVR Services, etc.
Thanks again!!
Chris