Research On Bandwidth Scheduling Algorithms For Advance Requests And Immediate Requests In High-performance Networks

In the current era of big data,a large amount of information is being generated every minute and every second in various fields.These data need to be transmitted to the designated data center for analysis through the network in time.With the increase of data volume and continuous improvement of Quality of Service(Qo S)requirements,the best-effort data transmission methods of traditional networks can no longer meet user needs.With the rapid development of Software Defined Network(SDN),High-Performance Network(HPN)with bandwidth reservation function is gradually recognized.This paper mainly studies the bandwidth scheduling problem of a group of advance reservation requests and the joint scheduling problem of advance reservation requests and immediate reservation requests under High-Performance Network.The scheduling success ratio and customer satisfaction degree are used as service quality indicators to prove the NP completeness of the problem.After proving the NP completeness of the problem,heuristic algorithms are designed and a large number of simulation experiments are performed.The research content mainly includes the following three aspects:(1)Regarding the bandwidth scheduling problem of a batch of advance reservation requests,it is proved that the problem is NP complete problem.In order to balance the use of bandwidth resources to transmit more user requests,preferentially using the time slot with the largest bandwidth resources,and design a heuristic algorithm based on this to further improve the overall scheduling success ratio.(2)For the joint scheduling problem of advance reservation requests and immediate reservation requests,it is proved that the problem is NP complete problem and design a heuristic algorithm.The problem involves two types of requests,they are advance reservation requests and immediate reservation requests.A batch of advance reservation requests is reserved using the heuristic algorithm in(1).For possible arrival immediate reservation request,the scheduling algorithm is designed according to the input parameters of the request.The main idea of the algorithm is similar to the algorithm in(1).If the current network resources cannot meet the data volume transmission requirements,the immediate reservation request will preempt the bandwidth resources of the reserved advance reservation requests.It also minimizes the occupied bandwidth while minimizing the number of occupied advance reservation requests,so that the remaining data can be transmitted in time.For the occupied advance reservation requests,the bandwidth scheduling algorithm is designed again to find a suitable reservation scheme.This algorithm increases customer satisfaction degree through the rational use of resources and the reprocessing of occupied advance reservation requests.(3)In order to evaluate the performance of the two heuristic algorithms,the classic VPVB algorithm and the greedy algorithm which designed based on the latest research progress of similar problem are used as comparison algorithms.The algorithms are executed in a real High-Performance Network topology and different networks with specified number of nodes and links.A large number of simulation experiments are performed.The experimental results show the superiority of the algorithms in this paper.