The system is MPLS enabled, making it technology agnostic. What goes in with an IP address goes through the cloud and comes out with the same IP address. So, yeah, VoIP could run over it. RoIP could run over it. It can send files. It can carry streaming video. It can carry telemedicine. It can carry biometrics. It can be combined with fiber to create modal diversity. Most of all, it created a connectivity commons that was severely lacking in the area. That vacuum made it impossible to build a more advanced voice radio network without astronomical cost of disaggregated links. It was intended to replace a number of discrete wired circuits, hub-and-spoke microwave, an old analog microwave system, and a hodge-podge of (for the lack of a better word) stuff. The system COULD serve as a backbone for the radio systems which had been initiated within the area, and COULD serve as a trunkline between various site controllers, but it is not only capable of that.
It should be several OC-3 loops that touch the seven counties in the region and the City of St. Louis (which under Missouri law is not a county). The original concept (dreamed up by a RR member in a now defunct Mexican restaurant off I-70 about 5 or 6 years ago, and refined by a committee comprised of several more RR members) was to touch each county at each EOC and primary PSAP (or to at least get to the lead primary PSAP in each county), and communications site. It grew into potentially carrying VDV for various applications. The original concept was to connect to the MSHP microwave system in Warrenton on the west, and the Illinois DOT microwave system in Collinsville, potentially linking the states together. The system concept changed quite a few times between grass roots support to what RCC Consultants developed as a spec.
I should note that the idea had intense competition for UASI funds from a helicopter, trailers, and other items, like shrinkwrap for dead bodies. One year it had its funding stripped. The gentleman qoted in the article wanted nothing to do with the idea in its early stages and the idea nearly went away if not for the tenacity of the committee which supported it. Many of those people are no longer involved in the program. Gotta love the sausageworks of politics.
As for system reliability, the committee had pushed for 6 9's of uptime on the microwave network (99.9999%) and the radio coverage was based on a DAQ of 4.0 throughout the entire covered region (~98% reliability). Yep. Soundbites.