代理集群的负载均衡系统设计与实现计算机科学与技术专业论文.docx

哈尔滨工业大学工学硕士学位论文 哈尔滨工业大学工学硕士学位论文 II II Abstract Proxy service is a necessary and common Internet services. It gives us several benefits, first is to provide better network services, such as network bandwidth because the advantages of a proxy server, it can speed up access. Second it can enhance our security, we do not communicate directly with the server by using proxy service, all traffic is forwarded through a proxy server, so that our host is not exposed to the network which, to enhance our access to the network security, security monitoring services which the agency provided to save us from being Trojans, and malicious code attacks. The third, proxy service is also a effective way for network management. Large flow proxy system forwards the biggest problem is retransmission efficiency. One of the methods to solve this problem is using multi-machine parallel to form a proxy cluster. Cluster there is a problem is how to make the flow evenly distributed to each server above. Load balancing is an important means to solve this problem one. In this paper, we introduced related research background. Then the relevant areas of research of load balancing, compared several common load balancing strategies, including random strategy, polling strategy, least connections strategy etc.. These strategies are directed at the initial balancing of the load, but the load balancing problem of proxy cluster is often happen when it’s already been assigned. Therefore, to solve load balancing issue under the agent cluster should focus on load migration. In this paper, we present a load migration algorithm for proxy cluster system. And implemented several common load balancing strategies under the application of the proxy cluster environment, and presents a better, more focused on the proxy system strategy, we did comparative experiments on the load balancing strategies that we implemented under proxy cluster system. Finally, we present a system can freely switch between the load balancin