The field of optical communications continues to evolve to meet the ever increasing demands for capacity, flexibility, scalability, and security. In this second installment of the Optical Communications Networks Series in 2016, we have selected six contributions that address physical layer security in optical networks, resource optimization in cloud-based radio over fiber networks, transceiver configuration in flex-grid optical networks, control plane architecture in multi-domain elastic optical networks, cost assessment of FTTdp networks with G.Fast, and hybrid ROADM architectures for scalable C/DWDM metro networks. Diverse topics addressed in this issue are indicative of the pervasive role of optical communications technologies in modern communications networks