One of our clients is a growing Florida-based insurance company whose board is highly concerned about disaster recovery. Although they have moved their infrastructure to a data center and have substantial equipment redundancies, one risk they weren't comfortable with was voice outages related to network problems or last-mile connectivity.
For a variety of reasons this client couldn't switch to SIP, which could alleviate some of the risk associated with connectivity. Even if they could have, though, they would still have risk associated with carrier network outages — rare, but not unheard of.
They experimented with ring-no-answer forwarding, but because their traffic is predominantly inbound, and because they provide policies under a number of different company names, those solutions created their own set of problem. In a forward scenario, the toll-free DNIS can't remain attached to the call. As a result, the failover caused serious problems for their PBX's call routing logic and prevented their customer service reps from seeing the opening scripts for that specific number.
What we did for them was set them up as their own resporg via a third-party service. Now they own the toll-free numbers and can make changes to those numbers' routing in the toll-free SMS/800 database. As a resporg, they can control all the routing options available via the SMS/800 database, and they can reserve their own numbers in real-time, including looking up vanity number availability.
The DR value is derived from the ability to change the carrier code associated with a given toll-free or set of toll-frees. If a network outage affects one carrier's voice network, or an access issue impacts our client's connectivity to one carrier, they can log into a web portal and reroute the affected toll-frees to a backup carrier, possibly in a different location altogether.
Because the database updates every 5-6 minutes, this design is truly extended DR. It's not designed to cover the 30 seconds Phil the phone guy accidentally unplugged their MUX. It's designed to mitigate extended network-related issues.
Another positive side effect is that because they own their toll-free numbers, moving traffic among carriers is almost immediate. This ability allows them to make quick changes to manage costs and prevents them from being held hostage should they choose to sever a relationship with one of their voice providers.
Best of all, this service is incredibly cheap. For this client it's less than 1% of their voice costs. If you have clients with similar requirements, let us know. We can help you to put together a similar solution.