The evolution of industrial communications, including mission-critical connectivity, is constantly requiring more and more throughput, or speed. Often the highest speed requirements are for less critical components, like video. The challenge is to combine speed and reliability requirements, and this often calls for efficiently combining different technologies, such as cellular and private radio networking technologies.
You need to make sure that the co-operation with adjacent technologies is seamless. If one communications channel, for example public network, becomes unavailable the switchover to surviving path is done automatically.