Real-time demonstration of industrial protocol applications by PHY softwarization for fully virtualized access networks

Abstract

To realize optical access networks that can flexibly and quickly accommodate a variety of new services, we need virtualization of the access systems targeting physical-layer (PHY) softwarization as well as the softwarization of management and control functions. Our previous demonstrations showed 10-Gbps-class passive optical network (PON) PHY implementations on general-purpose servers using graphic processing units. However, only the PON PHY application was considered. As a promising use case, the application of industrial protocols to access networks is being considered. PROFINET isochronous real-time (IRT), which is one such industrial protocol, sets the network requirements of 1-ms latency and 1-µs jitter. This paper builds and tests a demonstration platform that runs industrial protocols combined with Ethernet PHY and PON PHY on a general-purpose server. Ethernet PHY is newly implemented through our technique of parallelizing frame synchronization. To achieve the deterministic communications required by industrial protocols, cyclic transfer and time slot allocation are implemented in the platform. The demonstration results show that the platform achieves real-time software implementation of 10G Ethernet PHY and that our industrial protocol implementations satisfy the PROFINET IRT requirements of latency and jitter. This confirms that the softwarization of optical access systems is possible for applications beyond PON.