Research On The Design Of Link Selection And Load Balancing

In this information age,network has been developing rapidly. People’s demand for bandwidth is growing. To solve the reliability, stability and expand the bandwidth between enterprise networks and Internet,more and more companies choose to connect Internet through multiple links.Link load balance can not only deal with link failure and select the nomal link forwarding traffic,it can also realizes the efficient cooperation of multiple links and optimizes the overall throughput providing the best user experience. In this paper,we mainly focus on link load balance and link selection to optimize the system throughput.The main work includes:(1)In link loadbalancing respect,this paper is based on H3C’s outband link load balance project.This paper first analyses the functional requirements,then designs the framework of link loadbalance module,which can meet many kinds of load balance configuration requirements.Based on this loadbalance frame,we mainly focus on the design and realization of proximity function.Proxirnity scheme is based on the real situation of links, considering RTT、TTL、the remaining bandwidth、cost、user configuration weight and other factors. The proximity algorithm will process those information to get the totalcost and a ascending rank list of different links based on the totalcost.It will forward packets using the minimum totalcost link and get the proximity entries.At last this paper builds the experiment environment to test proximity function and analyses the results.(2)In the wireless link selection and load balancing respcet, the problem of station access are studied both in single AP and multiple AP situations.Firstly,in the case of single AP situation,IEEE802.11MAC access protocol only guarantee the fair access number, but not guarantee the fair access time of different stations,which results in the AP throughput anomaly. This paper puts forward a kind of algorithm to ensure time fair access,which can effectively improve the AP throughput. Then we continue researching the station access problem in multiple AP situation and proposing a multiple AP access method based on time fair in order to maximize the sum throught of all APs. The station is going to associated with which AP is controlled by the AC.Finally this paper builds NS2simulation environment and the simulation results show that the work of this paper achieves the expected target.