计算机网络(AndrewSTanenbaum)复习.docVIP

Andrew S. Tanenbaum. Computer Networks(Fourth Edition). 北京：清华大学出版社，2004. PAGE PAGE 68 COMPUTER NETWORKS FOURTH EDITION Andrew S. Tanenbaum 1 Introduction 学习目的：了解计算机网络发展历史、计算机网络的分类、网络体系结构（OSI/RM、TCP/IP）、计算机网络相关的基本概念和交换技术等。 学习重点：熟练掌握计算机网络、网络协议、网络体系结构等三个重要概念。 学习难点：掌握三种交换技术之间的异同。 Computer Network: A collection of autonomous computers（自主计算机） interconnected. Computer Network is composed of hosts, protocols and communication-subnet. The development of computer network:(additional) (1) First, Terminal-oriented network. Computing technology combine with communication technology. Circuit-exchange(电路交换): Connection establishment, Data transform, Connection release. (2) Second, Packet-exchange network: 1969.11, ARPANET Compare Circuit-exchange, Packet-exchange and Message-exchange (3) Architecture of network: ISO: OSI/RM(开放系统互连基本参考模型,Reference model) Internet: TCP/IP IBM: SNA(系统网络体系结构)，1974，the first architecture of network Digital: DNA(Distributed network architecture, 分布式系统体系结构) Uses of Computer Networks Business Application The goals of the computer network: Resource sharing（hardware and software资源共享） High reliability（高可靠性） Saving money（节约经费） Expansion（可扩充性） Communication medium（通信手段） 1.1.2 Public Application Access to remote information(访问远程信息) Person tom person communication(个人间通信) Interactive entertainment(交互式娱乐) E－commerce(电子商务) Mobile users(移动用户) 1.1.3 Social Issues 1.2 Network Hardware Broadly speaking(从广义上讲)，two types of transmission technology: 1. Broadcast links 2. Point-to-point links Broadcast network(广播式网络)：broadcasting and multicasting Point-to-point network(点到点网络)：packet－transmission(分组转发) and routing－algorithms（路由选择） 1.2.1 Local Area Networks(局域网) three characteristics: (1)Size(范围) (2)transmission technology(传输技术) (3)topology(拓扑结构) 1.2.2 Metropolitan Area Networks(城域网) 1.2.3 Wide Area Networks(广域网) 1.2.4 Wireless Networks System interconnection Wireless LANs Wireless WANs 1.3 Network Software 1.3.1 Protocol Hierarchies