  Only radio access networks can provide connectivity across multiple antenna
sites to achieve the great leap forward in capacity targeted by 5G. Optical
fronthaul remains a sticking point in that connectivity, and we make the case
for analog radio over fiber signals and an optical access network smartedge to
achieve the potential of radio access networks. The edge of the network would
house the intelligence that coordinates wireless transmissions to minimize
interference and maximize throughput. As silicon photonics provides a hardware
platform well adapted to support optical fronthaul, it is poised to drive smart
edge adoption. We draw out the issues in adopting oursolution, propose a
strategy for network densification, and cite recent demonstrations to support
our approach.
