PIE: A Lightweight Control Scheme To Address the Bufferbloat Problem

Document Type Replaced Internet-Draft (individual in tsv area)
Last updated 2015-10-14 (latest revision 2012-12-10)
Replaced by draft-pan-aqm-pie
Stream IETF
Intended RFC status Informational
Expired & archived
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Stream WG state (None)
Document shepherd No shepherd assigned
IESG IESG state Replaced by draft-pan-aqm-pie
Telechat date
Responsible AD Martin Stiemerling
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This Internet-Draft is no longer active. A copy of the expired Internet-Draft can be found at


Bufferbloat is a phenomenon where excess buffers in the network cause high latency and jitter. As more and more interactive applications (e.g. voice over IP, real time video streaming and financial transactions) run in the Internet, high latency and jitter degrade application performance. There is a pressing need to design intelligent queue management schemes that can control latency and jitter; and hence provide desirable quality of service to users. We present here a lightweight design, PIE(Proportional Integral controller Enhanced) that can effectively control the average queueing latency to a target value. Simulation results, theoretical analysis and Linux testbed results have shown that PIE can ensure low latency and achieve high link utilization under various congestion situations. The design does not require per-packet timestamp, so it incurs very small overhead and is simple enough to implement in both hardware and software.


Rong Pan (ropan@cisco.com)
Preethi Natarajan (prenatar@cisco.com)
Chiara Piglione (cpiglion@cisco.com)
Mythili Prabhu (mysuryan@cisco.com)

(Note: The e-mail addresses provided for the authors of this Internet-Draft may no longer be valid.)