Notes on the per-flow packet count flow classifier

To realize a packet count classifier, in addition to the active flow table, a candidate table is needed, where information on flow candidates is kept. We observe the temporal behavior of both the active flow table and flow candidate table size using actual traffic traces. The results indicate that the performance bottleneck in a packet count classifier lies within the candidate table management. Also, the changes in the candidate table size occur much faster than in the active flow table. Therefore, fast methods of creating entries and deletions in the candidate table are needed.