Traffic Sensitive Active Queue Management

1. Traffic Sensitive Active Queue Management Vishal Phirke, Mark Claypool, Robert Kinicki CS Department Worcester Polytechnic Institute Worcester, MA 10609, USA http://perform.wpi.edu/ ftp://ftp.cs.wpi.edu/pub/techreports/02-10.ps.gz

2. RED-Boston AQM Support for QoS • RED-Boston • Delay Hint • Moving Target • Weighted Insert

3. Using Delay Hints – An Example • T1 link • H.261 Videoconference

4. A Moving Target

5. The RED-Boston Algorithm • On receiving packet pkt: target = AdjustTarget(target, pkt.delay) if (qavg >= maxth) then dropPacket(pkt, 1) elseif (qavg >= minth) then p = calcDropP(qavg , minth, maxth, maxp) p’= p  (delayavg/pkt.delay) if (!dropPacket(pkt,p’)) then weight = arrival_time + pkt.delay insertPacket(pkt, weight) • Every interval seconds: if (qavg > target) then maxp +=  elseif (qavg < target) then maxp = 

6. Evaluation Set 1 Set 2 QoS = T / D  T is Throughput D is Delay  +  = 1

7. Evaluation: Set 1 Throughput Sensitive Normalized QoS (QoS = T1/D0) Delay Sensitive Normalized QoS (QoS = T0.5/D0.5)

8. Evaluation: Set 2 • Delay Hint • 1 0 • 0.917 0.083 • 0.834 0.166 • 0.75 0.25 • 0.67 0.33 • 0.584 0.416 • 16 0.5 0.5

9. RED-Boston Summary • Per-Flow QoS driven by Application • Scalable (No per-flow state required) • No monitoring, policing or shaping required • Compatible within DiffServ class or with current Best-Effort Internet Select References • S. Floyd, R. Gummandi, S. Shenker. “Adapative RED,” http://www.icir.org/floyd/papers/adaptiveRed.pdf, 2001. • P. Hurley, M. Kara, J.L. Boudec, P. Thiran. “ABE: Providing Low Delay within Best Effort,” IEEE Network Magazine, May/June 2001. • Vishal Phirke, Mark Claypool, Robert Kinicki. “Traffic Sensitive Active Queue Management,” Technical Report WPI-CS-TR-02-10, CS Department, WPI, May 2002. ftp://ftp.cs.wpi.edu/pub/techreports/02-10.ps.gz