非连通通信网络中的分布式优化算法

A distributed optimization algorithm in connection-less networks

本文考虑了非连通通信模式下互联网网络的带宽资源优化分配问题,其目标是使得网络中每个节点独立地将流量以最优方式分配给给定的一个或多个下一跳节点.注意到用户在使用某些应用时有非弹性的服务需求,故将网络效用函数建模为非凹的函数.最大化一类非凹的效用函数,也就是要解决非凸的优化问题.为了解决上述问题,本文设计了一个序列的优化问题,该序列的优化问题的解会收敛到原问题的最优解.基于上述优化问题,设计了一种分布式的流量分配算法.本文中的结果是基于实分析和凸优化理论等理论得到的.应用本文的算法可以使得每个节点独立地更新流量分配策略,并且仅用到最少的局部信息.最后,通过数值仿真验证了算法的有效性.

This paper considers the optimization problem of traffic allocation in a connection-less autonomous system.The objective is to enable each node in the network to independently distribute traffic among any given set of next hops in an optimal way.We model the network utility function with non-concave function because of users’inelastic requirements on data rates in some practical applications,such as video and audio streaming.Therefore,we tackle the problem of optimizing a generalized class of non-concave utility functions.To solve this problem,we first design a sequence of convex relaxations whose solution converges to that of the original problem.Then,we propose a distributed sending rate control algorithm to solve the convex relaxation problems.The approach taken relies on results from real-analysis theory and optimization theory.All computations required by the algorithm are performed independently and locally at each node using local information and minimum information exchange between neighboring nodes.Numerical simulations are performed to evaluate our results.