PC-DUOS: Fast TCAM lookup and update for packet classifiers

We propose algorithms for distributing the classifier rules to two TCAMs (ternary content addressable memories) and for incrementally updating the TCAMs. The performance of our scheme is compared against the prevalent scheme of storing classifier rules in a single TCAM in priority order. Our scheme results in an improvement in average lookup speed by up to 48% and our experiments demonstrate an improvement in update performance by up to 2.8 times in terms of the number of TCAM writes.