多出口网络链路负载均衡系统的研究

针对当前广泛使用的多链路技术,研究了多链路网络的运行机制,对多链路的流量特性、负载分配策略进行了分析.将企业网日常的Internet流量分为Outbound流量和Inbound流量,并结合FreeBSD下的PF包过滤和动态DNS解析技术,分别给出了Inbound和Outbound流量的负载均衡策略和模型.基于该模型研制的系统,能成功地依照事先定义的负载均衡策略实现Inbound和Outbound流量的负载均衡,多个Internet链路的合理分配利用而使得总访问带宽扩大,能够很好地消除几大ISP间互访的瓶颈,还为内部网上SERVER提供更高的可靠性和性能.

The link load-balance system of multi-homed networks

The multihomed technology is widely used nowadays. The traffic character and link load balancing strategies of multihomed networks were analyzed respectively. The enterprise＇s Internet traffics were divided into Inbound and Outbound traffics. Connected with the PF （packet filter under the FreeBSD） and DNS techniques, link load balancing policies and models respectively for Inbound and Outbound traffics were proposed. The system based on these models can realize load balancing of both Inbound and Outbound traffics according to the pre-defined policies. Traffics can be reasonably distributed into different links, which increases the overall bandwidth. It not only solves the bottleneck problem of mutual-visit among several ISPs, but also promotes the dependability and capability of the servers on the enterprise network.