Switches And Implementation Of Content-based Cluster System

With the popularization of broadband network and proliferating of people online, Internet has been rapidly increasing in recent years. Many Internet content providers are aware that using a single server to provide services hasn't met the need of increasing network bandwidth.Balancing network loads to some servers so as to provide the same service, cluster technology can increase the quality of service. The Layer-4 cluster technology based on IP address and TCP port is widely used for excellent transmission performance. However, as for Layer 4 switch, this cluster technology cannot examine the content of packet. For e-commerce and other services, it's not effective if packets cannot be switched according to the needs of the users. It may even lead to serious mistakes. So Layer-7 switch, called content switch, is used to satisfy the demands. It can not only transmit request packets to suitable server according to the content of user's request, but also support "session" based on content. It can be further applied to firewalls, Spam filters and so on.A prototype system of content switch has been developed ?Kernel Content Switch (KCS) on Linux. This system chooses HTTP protocol as application level protocol of content switch and Delay Binding as data transmission mechanism. It can not only feed the need of content switch based HTTP protocol, but also expand to support other application level protocols. This system validates the solution of content switch mentioned in the paper, but the performance should be further improved.