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A novel protection mechanism for local passive optical networks with bus topology and its verification

The most critical components of passive optical networks (PONs) are usually the central optical line termination unit (OLT) and optical fibers. That is why this article contains the description of a novel protection mechanism for designing of a local PON with a bus topology and enhanced network resilience. The idea is based on using dual OLT units together with contra‐directionally arranged passive splitters to form a bus topology. Thanks to that the resistance of presented PON solution against the potential malfunctions of OLT units as well as optical fibers is significantly increased. Since the application of asymmetric passive splitters is necessary to balance the attenuation and optical signal levels in the entire network, the mathematical model for calculating their optimum splitting ratios is presented as well. Moreover, the functionality of designed bus topology was verified by using real PON equipment and by performing complex measurements. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:2005–2010, 2014