| In the past few years,with the rapid development of the information technology,especially the development of the Internet,human society has stepped into the time of complex networks.Human’s manufacture and life deeply depends on the effective operation of various complex systems.Meanwhile,plenty of researchers try to do some research on the Internet,power network,communication network,biological network,financial network and social network from the perspective of complex network.A series of valuable phenomenon and theory have been found.This paper is mainly about the optimization of resource allocation and flow control in complex networks,especially in the communication network,optimization algorithms which adjust the node capacity and link bandwidth to maximize the total utility of the flow are given under both synchronous and asynchronous circumstances.And this kind of research may give some insights for resource allocation in real communication networks.This paper contains the following three outcomes:(1)With the background of the transmission mechanism in the real communication network,we come up with a more comprehensive concept-resource allocation.Combined with the congestion control protocol,we formulate an optimization problem which aims at achieving the best transportation performance under the constraints of capacity of nodes and bandwidth of links simultaneously.An iter-ative algorithm that adjusts transmission flow,capacity of nodes and bandwidth of links is proposed.(2)In the synchronous model,which assumes that the updates of sources and links are synchronized to occur at times t = 1,2,...,we proposed an iterative algorithm to adjust transmission flow,capacity of nodes and bandwidth of links at the same time and the convergence of this algorithm is proved.Meanwhile,the optimal transmission flow will increase linearly with the increase of total node capacity and link bandwidth when the derivative of utility function satisfies the formula As · xps.given A.is a constant and p E R.The mathematical proof is given as well.(3)To better resemble the reality of large networks,we extend the above-mentioned model to an asynchronous setting.An iterative algorithm to adjust transmission flow,capacity of nodes and bandwidth of links is given and the convergence of this algorithm is proved.And we also apply some indicator to measure the performance of our algorithm. |
