I do the same thing as dooBdoo, check online.
Its a complicated system, way beyond my knowledge base.
Last week my neighbor called me on his cell phone asking if we had phone service. We did, he didn't. He called a friend who works for Comcast, who told him the company was adding lines which was affecting the phone service for some customers. He had him unplug and replug his modem and the phones operated again.
It would be nice if they could initiate some notification system that would alert customers when they were experiencing issues.