Lecture, 2.5 credits, Lab，0.5 credit，3.5 hours per week. Pre-requisites: No.This course systematically introduces the development of the computer network and the principle of system structure, physical layer, data link layer, LAN, Wan, network interconnection, transport layer, application layer, computer network security and Internet evolution, focuses on in the various agreements. Through the study of this course, the students master the basic theory of computer network, network communication protocol and practical network technology, to lay the foundation for future work in this area.