MPCC:一种用于Ad Hoc网络多径路由的优化拥塞控制算法

MPCC: Optimal Congestion Control for Multipath Routing in Ad Hoc Networks

基于Ad hoc网络中信息流之间的竞争特点,引入了链路干扰集的概念,并将描述Internet中多径路由拥塞控制问题的多径效用最大化问题推广到Ad hoc网络中.由于多径效用最大化问题中的目标函数对路径速率而言不是严格凹的,所以运用罚函数法将此最大化问题转化成新的等价形式,再运用次梯度法获得了原问题的最优解,由此提出了用于Ad hoc网络的多径路由优化拥塞控制算法MPCC.链路和源节点能独立平行地执行该算法.仿真结果表明,MPCC能快速收敛到最优解,对网络状态的变化具有较好的自适应能力,所获得网络性能比TCP-Reno的AIMD算法要优越,因此适用于实际Ad hoc网络.

Based on the inherent characteristic of the contention relationship between flows in Ad hoc networks, a notion of the link＇s interference set is introduced, it extends the muhipath utility maximization formulating the congestion control problem for multipath routing in Internet to that in Ad hoc networks. As the objective function is not strictly concave in the path rate, the penalty function method is applied to transform the primal problem into a new formulation to obtain the optimal solution based on the subgradient method. And the multiPath congestion control algorithm （MPCC） is also proposed. It can be implemented in a parallel fashion at each source/link. Simulation results show that MPCC can quickly quickly converge to globally optimal solutions; and, compared to the additive-increase-multiplicative-decrease （AIMD） algorithm in TCP-Reno, MPCC is more adaptive to time-varying network situations, and achieves better network performance. And thus it can be used to the practical Ad hoc networks.