On the advantages of lifetime and RTT classification schemes for TCP flows

We exploit the isolation of TCP flows based on their lifetime (classified as shortor long-lived flows) to eliminate the impact of long-lived flows on the short-lived, achieving improved response time for short-lived flows. An additional classification scheme provides large-grain separation of flows with drastically different end-to-end round-trip-times (RTTs). The scheme provides long-term fairness among the long-lived flows. Hence, the combined lifetime and RTT classification appears to be able to provide both fair bandwidth sharing and better response time for the long-lived and short-lived flows respectively. The presented evaluation results suggest that the combined classification performs, under all tested case, comparably or better than RED. The results indicate that a classification scheme together with some not-perfectly tuned RED, or even with DropTail dropping policy, can avoid the complexity of having to properly parameterize RED while achieving equal or better performance.