When Are Online and Offline Excess Bandwidth Distribution Useful in EPONs? (Invited Paper)

Excess bandwidth distribution techniques have recently been proposed to improve the dynamic bandwidth allocation in EPONs. We compare existing offline excess bandwidth distribution with conventional IPACT Limited in terms of packet delay performance. We identify the factors that result in packet delay reduction with excess bandwidth distribution compared to IPACT-Limited and discover that existing offline excess distribution mechanisms become unstable at moderate to high loads in long-range EPONs with large round trip propagation delays. We propose and evaluate a novel Online Excess Bandwidth Distribution (OEBD) mechanism to provide stable excess bandwidth distribution even at high loads in long-range EPONs.