FiWi network throughput-delay modeling with traffic intensity control and local bandwidth allocation

Fiber-Wireless (FiWi) networks typically combine an optical access network with a wireless access network so as to build on the respective strengths of the optical and wireless network technologies. Prior analytical throughput-delay studies of FiWi networks have typically considered heavy-loaded traffic models, i.e., constantly backlogged source nodes. In contrast, in this paper we present a more general comprehensive FiWi network throughput-delay analysis that encompasses Poisson (non-heavy) as well as heavy-loaded input traffic models. In addition, our analysis covers bandwidth assignments of wireless channels both at the hop distance level and at the node level, as well as a queuing model of dynamic bandwidth allocation in the optical access network. Our analysis provides insightful guidelines for setting the channel access probabilities for source traffic and relay traffic in FiWi networks. Our numerical evaluations demonstrate that prior studies which considered only heavy traffic loads gave misleading results for the delay performance of well-known access probability assignments. We correct and clarify these misleading results with our more general analysis for nonheavy traffic.