Revisiting Old Friends: Is CoDel Really Achieving What RED Cannot?
Résumé
We use ns-2 simulations to compare RED's gentle_ mode to CoDel in terms of their ability to reduce the latency for various TCP variants. We use a common dumbbell topol- ogy with Pareto background traffic, and measure the packet delays and transmission time of a 10 MB FTP transfer. In our scenarios, we find that CoDel reduces the latency by 87 %, but RED still manages to reduce it by 75 %. However, the use of CoDel results in a transmission time 42 % longer than when using RED. In light of its maturity, we therefore argue that RED could be considered as a good candidate to tackle Bufferbloat.