a method for configuring service curves for managing the output port of a networking device includes the following steps . a multitude of traffic classes is defined , each traffic class being characterized by a bandwidth and a delay priority . a multitude of traffic service curves is computed , each of the plurality of traffic service curves is associated with a different one of the multitude of traffic classes . at least one of the multitude of traffic classes service curves is characterized by a shifted two - piece linear function shifted such that the service curve limits service to during a nonzero time period prior to the start of the two - piece linear function .