The Design And Implement Of Resource Allocation Mechanism In Software Defined Satellite Network

To date,satellite networks are contained-designed,inflexible for configuration update and can’t provide on-demand services. Traditional network architecture haven’t dealt with these problems,however,the emerging network architecture——Software Defined Network (SDN),which can provide satellite networks with high efficiency and fine-grained control by decoupling the data plane and control plan.Therefore,the application of SDN architecture in satellite networks is an research area of concern.This paper is supported by the The National 863 Project:Key Technologies and Demonstrations of Future Integrated Network (NO.SQ2015AA015702),which is proceeding in our lab.Basing on the Software Defined Satellite Network(SDSN) architecture presented in the Project,this paper futher presents a kind of resource allocation mechanism adapted to satellite networks,the communication scenario refers to a broadband multimedia communication system called Space Way.In this paper,the users in multimedia satellite communication scenario are divided into four levels,including voice,video,critical business and best effort data,which listed from high to low priority.Resource allocation mechanism aims to allocate resource to users at different level to satisfy their QoS demands and it consists of two parts.One is flow allocation:it differentiates service level of flows according to tos and results in a Resource Costs Metric function for each link.The function is inputed to the shortest-path calculation module as a link weight,which exports a optimal resource allocation route.Another is bandwidth allocation containing two shared-link conditions that multiple same-level flows and different-level flows with the same flow allocation result.On the data plane,software switches set qos queues according to the Double Boundary Movable Method presented in this paper.On the control plane,controller choose the queue id dynamically.These two parts assure the fairness and effectiveness of resource allocation.Resource allocation is realized in POX controller as a customized component, including link states monitor,flow allocation and bandwidth allocation modules.Among,the link states monitor collects link latency,data rate and loss packets number to supply the flow and bandwidth allocation,guaranting the accuracy of this mechanism.To analyze and verify the resource allocation mechanism,this paper set up a simulation environment based on mininet,and a experiment environment based on theDelay Tolerant Network architecture (DTN).The simulation models the communication scenario based on Space Way and implements functional tests about resource allocation preliminarily.The experiment uses ION, a platform realizing the DTN architecture,to simulate satellite communication environment.And by analyzing performances of effective throughput and transportation latency,it verifies the SDSN resource allocation mechanism presented in this paper can be combined with DTN protocol stack effectively.Thus, it is proved that the SDSN resource allocation is a reliable mechanism adpated to satellite networks.