I have a small business client that uses Time-Warner Cable for their internet access and their VOIP phones. They have had a couple of incidents in the last 2 years where their internet went down completely and was not restored for several days, losing them a lot of business. They would like to implement some sort of failover system whereby if Time-Warner goes down another system will kick in automatically to continue providing broadband internet.
I'm thinking of having DSL installed as a backup system. My question is how can I implement this so that if the cable service goes down, the DSL will automatically kick in and take over providing high-speed internet?