This article provides insight on two of the most relevant applications driving the design of the future MAN: the implementation of 5G by means of C-RAN (Cloud - Radio Area Network) and the deployment of edge computing. The work addresses important questions such as the target latency budget for future MANs, the target bandwidth requirements for 2020-2030 induced by 5G midhaul and fronthaul traffic, and describes how optical and electronics layers can co-operate to meet the QoS targets of C-RAN and edge computing traffic. In the process, we identify the key architectural elements to meet the challenges of these applications in a cost-effective way.
Innovative photonic solutions designed and developed in the H2020 research project PASSION are presented for the future metropolitan area network (MAN) supporting different aggregated data traffic volumes and operating at heterogenous granularities. System performance evaluated both by simulations and experimentation regarding the proposed vertical cavity surface emitting laser (VCSEL) -based modular sliceable bandwidth/bitrate variable transceiver (S-BVT) are shown in realistic MANs organized by hierarchical levels with the crossing of multiple nodes characterized by new switching/aggregation technologies. The capabilities and challenges of the proposed cost-effective, energy-efficient and reduced footprint technological solutions will be demonstrated to face the request of huge throughput and traffic scalability.