In bidirectional fiber both forward and backward signal propagation should have to meet at same time ( as like real time) but in simulation it is not possible due to some operation being on either direction . in order to meet system as like real time here we introduce delay ,which will hold the signal propagation in fiber up to the completion of any operation on both side and make the signals meet the fiber at same time. the delay time is assigned it self by finding the processing time of number of component with in the operation.
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