Rights statement: The final, definitive version of this article has been published in the Journal, Computer Networks 57 (17), 2013, © ELSEVIER.
Submitted manuscript, 462 KB, PDF document
Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
}
TY - JOUR
T1 - Congestion control of TCP Flows in internet routers by means of index policy
AU - Avrachenkov, Konstantin
AU - Ayesta, Urtzi
AU - Doncel, Josu
AU - Jacko, Peter
N1 - The final, definitive version of this article has been published in the Journal, Computer Networks 57 (17), 2013, © ELSEVIER.
PY - 2013/12/9
Y1 - 2013/12/9
N2 - In this paper we address the problem of fast and fair transmission of flows in a router, which is a fundamental issue in networks like the Internet. We model the interaction between a TCP source and a bottleneck queue with the objective of designing optimal packet admission controls in the bottleneck queue. We focus on the relaxed version of the problem obtained by relaxing the fixed buffer capacity constraint that must be satisfied at all time epoch. The relaxation allows us to reduce the multi-flow problem into a family of single-flow problems, for which we can analyze both theoretically and numerically the existence of optimal control policies of special structure. In particular, we show that for a variety of parameters, TCP flows can be optimally controlled in routers by so-called index policies, but not always by threshold policies. We have also implemented index policies in Network Simulator-3 and tested in a simple topology their applicability in real networks. The simulation results show that the index policy covers a big range of desirable properties with respect to fairness between different versions of TCP models, across users with different round-trip-time and minimum buffer required to achieve full utility of the queue.
AB - In this paper we address the problem of fast and fair transmission of flows in a router, which is a fundamental issue in networks like the Internet. We model the interaction between a TCP source and a bottleneck queue with the objective of designing optimal packet admission controls in the bottleneck queue. We focus on the relaxed version of the problem obtained by relaxing the fixed buffer capacity constraint that must be satisfied at all time epoch. The relaxation allows us to reduce the multi-flow problem into a family of single-flow problems, for which we can analyze both theoretically and numerically the existence of optimal control policies of special structure. In particular, we show that for a variety of parameters, TCP flows can be optimally controlled in routers by so-called index policies, but not always by threshold policies. We have also implemented index policies in Network Simulator-3 and tested in a simple topology their applicability in real networks. The simulation results show that the index policy covers a big range of desirable properties with respect to fairness between different versions of TCP models, across users with different round-trip-time and minimum buffer required to achieve full utility of the queue.
KW - cs.NI
KW - cs.PF
KW - Active Queue Management (AQM)
KW - Markov decision process
KW - TCP modeling
KW - Index policies
KW - Whittle index
U2 - 10.1016/j.comnet.2013.08.001
DO - 10.1016/j.comnet.2013.08.001
M3 - Journal article
VL - 57
SP - 3463
EP - 3478
JO - Computer Networks
JF - Computer Networks
SN - 1389-1286
IS - 17
ER -