Analysis and applications of r-for N protectionsystem

摘要

The availability of a single member of a group of Nfunctionally identical systems that work in parallel and share a pool ofr backup systems is analyzed. These N+rsystems, each with failure rate λ, are repairable, and thereare m repairers available, each operating at rate μ. AMarkov model is used to derive formulas for availability, mean time tofailure, and mean time to repair for such a system. The analysis resultsindicate that by increasing r and decreasing ρ, the ratioof failure rate to repair rate, overall network availability isimproved. It is shown that, for certain ρ's, some r:N pooled protections can significantly outperform 1:1 or 1:2dedicated protection in terms of availability. The application of r:N protection to high-capacity transport systems isdiscussed, and it is indicated that multiwavelength systems may useadditional wavelengths for protection. It is concluded that r:N protection can potentially provide both improved availabilityand significant cost advantages to the high-capacity transport systems