Exact, approximate, and recursive blocking in all-optical networks

We present one exact and two approximate methods for calculating blocking probabilities in an all-optical network with arbitrary placement of wavelength converters. The exact method is most useful for short paths (no more than 4 links), while the first approximate method is useful for slightly longer hop paths (no more than 6 links). The second approximate method is based on a recursion and can be applied to arbitrary length paths. A simple wavelength converter placement policy is described and implemented using the blocking models in an example using the CA*Net II topology