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Abstract-Minimizing SONET ADM costs in single-hub SONET/WDM ring networks via traffic grooming has been discussed in a number of recent works. Recent work [12] gives the exact minimum costs of uniform traffic in both UPSR and BLSR/2 and proves that the BLSR/2 would never be more expensive than UPSR under any traffic pattern, if all wavelengths have same capacity.In this paper we consider how to groom both uniform and non-uniform traffic to minimize the cost of ADMs in the single-hub UPSR and BLSR/2 with mixed line speeds. We especially explore the grooming of traffic when wavelengths have two different capacities respectively, we provide optimal traffic partition and grooming for uniform traffic demands, and develop optimal or suboptimal solutions for non-uniform traffic demands, depending on the range of all demands from non-hub nodes.