I'm am looking to configure thirteen locations currently on MPLS - using Cisco881G backup routers with 3G cards.
I have two options: either IPSEC to the firewall or DMVPN to our core ASR.
The two 881G routers I have - one came with a Verizon 3G card and one with a Sprint - I can basically use either for my test router, but from what I've read, there may be some issues with these early deployed cards (we purchased the routers and cards early on but have not had a chance to use them). Also, I'm testing this on a point-to-point (proof of concept + access to both routers) but I'm assuming I can get the MPLS provider to comply with required changes on their equipment.
I'm looking for feedback on which way to go - IPSEC to FW or DMVPN to ASR. I was also thinking of using HSRP with the MPLS routers. Will EIGRP be the routing protocol to switch between the networks? We have a managed MPLS - so I do not have direct control over those routers.
Thanks for any assistance and direction you can provide.