I'm at a small ISP, and we currently not using MPLS at all. In the past, we have setup VPN tunnels for our customers with multiple locations and that has worked well. We have a customer who has two locations and some equipment co-located in our data center, and we have a hub-spoke VPN topology between their two locations and the data center (2611XM at client locations, Pix 515e in client rack in data center). However, they are putting in a shoretel phone system, which apparently will not function properly over the Cisco VPN and their phone vendor is telling them that they need to use an ISP who can provide MPLS. I've looked into setting up MPLS, and obviously we would have to upgrade the customer CPEs to at least 2821s, but I have some questions:
1)I have attached a simplified network diagram (obviously I have changed IP addresses, but topology matches), including all the hops that the customer traffic would take. Would I have to enable MPLS on each device, even the layer 2 switches?
2)What would a "best-practice" MPLS deployment look like?
3)Could I tunnel the MPLS directly from the customer premise equipment to a top of rack CPE in data center?