Multi-OLT PON-based open access network for multi-service performance tuning via the Event-Horizon algorithm

Abstract

A multi-optical line terminal (multi-OLT) passive optical network (PON) is gaining attention for its multi-access, wide coverage, and integration capabilities. It outperforms conventional single OLT PON, reducing operational complexities, packet delay, and loss. A novel multi-OLT PON-based open-access network (OAN) architecture is proposed that integrates various service providers (SPs) as well as different access networks. Optical network unit structure is also designed to support differential access. The challenging issue here is to incorporate heterogeneous SPs and provoke downstream service with their application diversity. This paper presents what we believe is a novel algorithm named Event-Horizon (EH) to afford heterogeneous downstream services from different SPs for IEEE PONs [Ethernet PON (EPON) and 10 gigabit EPON (10G EPON)]. It incites SP competitiveness and ensures a user experience of seamless migration from service to service. Downstream resource allocation is an atypical issue in the PON area. There are reported numerous online schemes with prediction for the upstream side. Since network data is highly bursty and unpredictable, the EH algorithm uses the machine-learning-based bootstrapping method as its prediction tool. The algorithm improves downstream performance by four distinctive features. First, bandwidth is guaranteed among shared SPs according to service level agreements. Second, bandwidth is allocated for reported data; then excess bandwidth is reallocated as predicted (by bootstrapping) differed data. Third, a donor SP preserves margin before excess bandwidth release, which is a nonlinear process featuring network dynamics. Fourth, the margin satisfaction factor is formulated for tuning multi-service user satisfaction according to quality of service. The simulation is performed by a model OAN showing an emergency medical wireless sensor network (WSN) as the master shareholder OLT and a fiber to the home (FTTH) as a subsidiary one. Performance tuning on the margin reservation of 1% for the WSN case study shows 99.4% network efficiency with maximum jitter of 50 µs up to the full load owing 97.26% throughput. Network delay justifies CISCO and ITU-T requirements for real-time IP traffic. FTTH experiences the packet loss of 0.68% using the EH algorithm at the full load, maintaining WSN emergency service packet loss<0.003%.