Preliminary simulation results on differentiated QCN

1. Preliminary simulation results on differentiated QCN Marina Lipshteyn

2. The scenario 4 Reaction points which transmitted constantly 3.8Gbs to 1 congestion point with pkts size - 0.5KB. Among them, one “victim” TCP session. Victim flow – TX 3.8Gbs CP 3.8Gbs 3.8Gbs 3.8Gbs

3. With PFC, without QCN The incoming traffic is reduced to: 2.3Gbs 2.3Gbs 2.3Gbs 2.7Gbs

4. With PFC and QCN The incoming traffic is reduced to: 3.8Gbs 1.6Gbs 2.3-1.8Gbs 2.3-1.8Gbs

5. Using different types of traffic Only one of the Reaction Points is injecting traffic above commited rate. In my opinion, it is more correct to pause that Reaction Point only. policer Victim flow – TX 3.8Gbs policer policer policer Overcommited traffic CP 3.8Gbs 3.8Gbs 3.8Gbs

6. Differentiated QCN at the Congestion Point At the Congestion Point define two thresholds for the queue: • The first threshold: When number of bytes in the queue exceeds it, send CNM ONLY IF the probed packet is YELLOW. • The second threshold: When number of bytes in the queue exceeds it, send CNM for any probed probed packet

7. With PFC and differentiated QCN The incoming traffic is reduced to: 3.8Gbs 2.3Gbs 1.6Gbs Overcommited traffic 3.8Gbs