I'm new to Orion and I need to assist my networking team with knowing when a carrier network (AT&T, Verizon, etc) is having issues. What module or combination of modules would be best to detect problems before our end users do?
NPM should be able to give you the info you need. But what do you see when you have a carrier issue? Link down? Syslog message? Depending on what happens in your monitoring environment when there are issues, that's how you alert on it.
Yes you're good with NPM. Use a NetPath to google (Part of NPM) and create an alert on it. Here is an article how to do that in the Success Center