Wireless networks of today have become a complex mix of various different flavors of services. Big macro networks can no longer become the sole provider of services but will become a conduit for heterogeneous networks and become a ‘backhaul’ for many services that will happen over the years. With a limited spectrum scenario it looks like a bleak future for wireless networks unless a smart strategy to inter-operate wireless with various protocols and software to overcome this. HetNets are evolving as we speak and implementation is a complex mix of various 3GPP and IEEE networks. Atleast in terms of 3GPP we are now backward compatible and there is convergence with LTE, though the bands of operation are fragmented and cumbersome for one phone to work worldwide.
M2M is probably the first implementation of wireless other than providing voice or data access to a live user. Wireless monitoring of fleets and SCADA devices on 2G networks is how it all started. ..