TY - GEN

T1 - Distributed rate allocation for inelastic flows

T2 - IEEE INFOCOM 2005

AU - Chiang, Mung

AU - Zhang, Shengyu

AU - Hande, Prashanth

PY - 2005/10/7

Y1 - 2005/10/7

N2 - A common assumption behind most of the recent research on network utility maximization is that traffic flows are elastic, which implies that their utility functions are concave and there are no hard limits on the rate allocated to each flow. These critical assumptions lead to tractability of the analytic models of utility maximization, but also limits applicability of the resulting rate allocation protocols. This paper focuses on inelastic flows and removes these restrictive and often invalid assumptions. We present several optimization frameworks, optimality conditions, and optimal algorithms. First, we consider nonconcave utility functions, which turn utility maximization into nonconvex, constrained optimization problems that are well-known to be difficult. We present conditions under which the current standard price-based distributed algorithm can still converge to the globally optimal rate allocation despite nonconcavity of utility functions. In particular, continuity of price-based rate allocation at all the optimal prices is a sufficient condition for global convergence of rate allocation by the standard algorithm, and continuity at at least one optimal price is a necessary condition. In the second part of the paper, we provide a general problem formulation of rate allocation among time-sensitive flows from real-time and streaming applications, as well as a decomposition into subproblems coordinated by pricing. After simplifying the subproblems by leveraging the optimization structures, we highlight the difficult issues of causality and time-scale, and propose an effective price-based heuristics for admission control and an optimal algorithm for a special case formulation.

AB - A common assumption behind most of the recent research on network utility maximization is that traffic flows are elastic, which implies that their utility functions are concave and there are no hard limits on the rate allocated to each flow. These critical assumptions lead to tractability of the analytic models of utility maximization, but also limits applicability of the resulting rate allocation protocols. This paper focuses on inelastic flows and removes these restrictive and often invalid assumptions. We present several optimization frameworks, optimality conditions, and optimal algorithms. First, we consider nonconcave utility functions, which turn utility maximization into nonconvex, constrained optimization problems that are well-known to be difficult. We present conditions under which the current standard price-based distributed algorithm can still converge to the globally optimal rate allocation despite nonconcavity of utility functions. In particular, continuity of price-based rate allocation at all the optimal prices is a sufficient condition for global convergence of rate allocation by the standard algorithm, and continuity at at least one optimal price is a necessary condition. In the second part of the paper, we provide a general problem formulation of rate allocation among time-sensitive flows from real-time and streaming applications, as well as a decomposition into subproblems coordinated by pricing. After simplifying the subproblems by leveraging the optimization structures, we highlight the difficult issues of causality and time-scale, and propose an effective price-based heuristics for admission control and an optimal algorithm for a special case formulation.

UR - http://www.scopus.com/inward/record.url?scp=25644432839&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=25644432839&partnerID=8YFLogxK

U2 - 10.1109/INFCOM.2005.1498551

DO - 10.1109/INFCOM.2005.1498551

M3 - Conference contribution

AN - SCOPUS:25644432839

SN - 0780389689

T3 - Proceedings - IEEE INFOCOM

SP - 2679

EP - 2690

BT - Proceedings - IEEE INFOCOM 2005. The Conference on Computer Communications - 24th Annual Joint Conference of the IEEE Computer and Communications Societies

A2 - Makki, K.

A2 - Knightly, E.

Y2 - 13 March 2005 through 17 March 2005

ER -