Title :
Understanding CHOKe
Author :
Tang, Ao ; Wang, Jiantao ; Low, Steven H.
Author_Institution :
California Inst. of Technol., Pasadena, CA, USA
Abstract :
A recently proposed active queue management, CHOKe, is stateless, simple to implement, yet surprisingly effective in protecting TCP from UDP flows. As UDP rate increases, even though the number of UDP packets in the queue rises, its bandwidth share eventually drops to zero, in stark contrast to the behavior of a regular FIFO buffer. We derive a detailed model of CHOKe that accurately predicts this, and other behaviors of CHOKe, and validate the model with simulations. Its key features are the incorporation of the feedback equilibrium of TCP with dropping probability and the spatial characteristics of the queueing process. CHOKe produces a "leaky buffer" where packets can be dropped as they move toward the head of the queue. This leads to a spatially nonuniform distribution of packets and their velocity, and makes it possible for a flow to simultaneously maintain a large number of packets in the queue and receive a vanishingly small bandwidth share. This is the main mechanism through which CHOKe protects TCP from UDP flows.
Keywords :
Internet; buffer storage; packet switching; probability; queueing theory; telecommunication network management; transport protocols; CHOKe; FIFO; Internet; TCP packet; UDP flows; active queue management; dropping probability; first in first out buffer; leaky buffer; nonuniform packet distribution; transport control protocol; user datagram protocol; Bandwidth; Communication system traffic control; Current measurement; Feedback; Inductors; Internet; Predictive models; Protection; Technology management; Traffic control;
Conference_Titel :
INFOCOM 2003. Twenty-Second Annual Joint Conference of the IEEE Computer and Communications. IEEE Societies
Print_ISBN :
0-7803-7752-4
DOI :
10.1109/INFCOM.2003.1208664
