Resource Allocation Study Based On Wardrop Equilibrium For Service Overlay Network

Service Overlay Network is currently one of the most promising architectures to provide end-to-end Quality of Service guarantees in the internet,without requiring significant changes to the underlying network infrastructure.SON is the application-layer network built on the top of the traditional IP-layer networks,it is operated uniformly by a third-party ISP(Internet Service Provider)domains,which owns a set of overlay nodes residing in the underlying ISP domains,these overlay nodes are interconnected by virtual overlay links,and perform service-specific data forwarding and control functions.SON benefits by establishing an economic relation with underlying ISPs and users,SON sets up special overlay nodes via bilateral service level agreement,and purchases some bandwiths from the underlying network,also provides end-to-end QoS guarantees value-added service to gain economic profit.Compared with the existing networks,Service Overlay Network has a large number of advantages.In addition to its ability to deliver end-to-end QoS sensitive services,it can decouple service request from underlying network,thereby reducing the complexity of network service management and control,especially in terms of QoS management and control. Overlay nodes select appropriate virtual links to transfer services adaptively.Using Service Overlay Network,we will be able to provide more reliable and fault-tolerance and better network services with no large-scale changes to the software and hardware of the undetlying internet.Because of its service awareness,an SON can deploy service-specific provisioning, resource management and QoS control mechanisms to optimize its operations for its services.Hence,the SON architecture not only simplifies the network QoS management and makes it more scalable,but also enables flexible creation and deployment of new services.This thesis is devoted to the study of Service Overlay Network problem of bandwidth allocation based on wardrop equilibrium.and it is also the focal point of this thesis.In this thesis,we put Service Overlay Network as overlay network platform.an architecture of Service Overlay Network is proposed,we mainly study bandwidth allocation problems satisfying QoS requirements,coming up with an adaptive bandwidth management strategic model of Service Overlay Network,which is divided into two parts:on the one hand,we apply Wardrop user equilibrium which is practical widely in traffic network to communication network,obtaining flow distribution of SON virtual links;on the other hand,we utilize flows and user QoS requirements,as well as available bandwidth derivation algorithm of virtual links,thus when the user give an premise of QoS requirement,we can get we buy at least how much bandwidth from underlying ISP by the derivation algorithm.Bandwidth allocation of SON network can be divided into fixed demand bandwidth allocation and dynamic demand bandwith allocation,in fixed demand bandwidth allocation,avaliable bandwidth vairation of SON virtual links is described by uniform distribution,bandwidth management framework satisfying QoS requirement is proposed, bandwidth allocation of background flows and without background flows are simulated by TransCAD,the simulation results provide minimum bandwidth provisioning satisfying QoS requirement.In dynamic demand bandwidth allocation,dynamic bandwidth resizing period of SON network is one resizing window,we predict traffic demand at the end of each resizing window for the next one,and performing bandwidth adjustment and allocation.we propose provisioning schemes of the Gaussian model,periodical measurements,and traffic predictions,puting forward two schemes,making use of binary search algorithm to predict and allocae bandwidth.Finally two schemes are simulated by NS-2,realizing dynamic bandwidth provisioning.