The third chapter presented a architecture of large-scale distributed hierarchical e-mail server with the solution of double load balancer based on NAT for E-mail system.

• 第三部分为集群电子邮件系统的体系结构，讲解了层次化的群电子邮件系统的体系结构，描述了双负载均衡服务器的集群邮件系统的解决方案。