异构网络中贪婪资源分配策略的研究

针对当前异构网络中多种业务并存的现状,提出了一种可应用于由移动微波存取全球互通和通用移动通信系统组成的异构网络中考虑切换业务优先的贪婪资源分配策略,并通过网络中的呼损率验证了该策略的可行性；接着,在NS2环境下将该策略与公平资源分配策略在资源利用率、分组丢失率方面进行了比较.仿真结果显示,新策略可以提供良好的服务质量,前者的资源利用率和分组丢失率比后者分别改善了13％和14％左右.

Research of greedy resource assignment in heterogeneous networks

The future beyond 3rd generation(B3G) or fourth generation(4G) mobile networks will consist of heterogeneous networks,such as Worldwide Interoperability for Microwave Access(WiMAX) and Universal Mobile Telecommunications System(UMTS).Mobile users can move freely between heterogeneous networks,using terminals with multiple interfaces.The most important issue in such networks is the best connectivity to applications anywhere at anytime.A greedy resource assignment scheme(GRAS) is proposed,which is implemented in a heterogeneous network consisting of WiMAX and UMTS.With GRAS,handoff traffics are assigned higher priorities among all traffics while requesting the network resource.Furthermore,GRAS is validated by calculating call loss ratio.The performances in terms of resource utilization and packet loss ratio are compared between GRAS with another scheme,named Fairness Resource Assignment Scheme(FRAS).Simulations results show GRAS could provide a better Quality of Service(QoS).With GRAS,the resource utilization is improved about 13%,and the packet loss ratio is reduced about 14%.