Thank you for the response.SECOM is a microwave network utilized by the Philadelphia region UASI counties to implement cross system patches for interop. It also provides other benefits on the back end.
The patching can be of limited use for responding entities if the response area is on the fringe or outside the coverage footprint of their home system.
It would make much more sense for the regional counties to continue making forward progress on cross programming of radios on multiple systems. For whatever reason, this has been a major hurdle for the region to overcome.