Design and Implementation of a High Performance Content Filtering Gateway

By using NetGraph kernel components and based on Unix v-flow design concept,a high-performance content filtering gateway was developed.Gateway packet capture frame is a directed graph which composed a series of NetGraph nodes connected together,packet can flow between different nodes along the graph edge,packet capture was accomplished through zero-copy technology in kernel space.Meanwhile an improved AC multi-pattern matching algorithm is used to accelerate the speed of keyword inspection and system performance in content inspection module.