Impact of physical layer configuration on availability of path protected optical fibre transmission network

The paper presents a new availability model and method of calculating path protected network availability, using the parameters which describe the impact of cable network construction on overall availability. Based on previous studies and analysis of data on real optical fibre network failures and physical layer configuration, we defined and classified weighting factors. Presented algorithm for availability calculation of path protected network, which include weighting factors, allows us to find optimal paths according to defined criteria. Sensitivity analysis is used to determine how "sensitive" a mean down time is to changes of weighting factors introduced to presented model. The obtained results are comparable with simulation results for idealized network cases with implementation of path protection. Proposed approximate method is favourable for a fast and objective availability estimation of observed network without the requirement for sophisticated tools and software.