Most sites, which have 10 to 20 people with PCs and phones, are connected via a single T-1, meaning if that link goes down operations are severely hampered. The failure that pushed Eaton to look for new answers was a 10-day outage at one of the rail car repair shops that stemmed from a hand-off problem between Verzion, the MPLS provider, and CenturyLink, the local link provider.

"We had SLAs but they just pro-rate the service fees and give you back a few hundred dollars," Eaton says. "The downtime, on the other hand, can cost you thousands upon thousands."

Eaton quickly ruled out dial-up as a suitable backup plan, but considered adding cellular modules to its remote routers, but determined that that would be too costly.

What's more, the company had another demanding capacity need pending: It wanted to add at some remote sites and move away from an expensive video surveillance service. That would make link reliability even more important and drive up bandwidth needs.

Ultimately Eaton became aware of Talari, which sells appliances that would let him add DSL or cable modem links to each site for redundancy, while also using the secondary links in a load-balancing scenario instead of just reserving that bandwidth for backup. The appliances constantly assess the quality of both links and route traffic accordingly.