Shared networks will become essential to the commercial viability of future mobile broadband operators, but progress has, in reality, been slow, and that has been a major barrier to mass deployment of dense networks. The twisted saga of Mexico’s plan for a shared 4G network is a good example of the factors which are holding back shared or wholesale RANs – even though these could revolutionize the economics of 4G, and will be essential to make any sense of the business case for 5G. In some areas, governments have encouraged or mandated shared macro networks to lower the cost of deploying 4G and so accelerate roll-out of mobile broadband services. However, from Russia to Kenya, these projects have foundered on…