CAPEX and OPEX simulation study of cost-efficient protection mechanisms in passive optical networks

The significance of broadband access networks has increased nowadays due to higher bandwidth demands required by new services. Passive Optical Networks (PONs) are believed to be the best technology for deploying broadband access networks. As new services evolve, end-users also expect PONs to be highly dependable. Yet, operators are not willing to deploy protection in access networks unless it is cost-efficient. Hence, this paper aims at performing a thorough cost analysis of different protection mechanisms in PONs. PON physical layout, infrastructure sharing and design decisions are captured by means of a network geometric model. Also, the dynamic dependability behavior of PONs is modeled with the aid of a Markov cost model. Monte Carlo simulations are used to evaluate the whole model. This way, a novel protection mechanism for PONs is proposed and assessed. Based on the results, the most cost-efficient protection scheme for PONs is identified. Finally, an important trade-off between Capital Expenditures (CAPEX) and dependability-related Operational Expenditures (OPEX) regarding PON physical layout is presented and solved, giving guidelines for designing PONs where the total cost is reduced.