文档介绍：复****题型?一、选择题(共20分)?二、填空题(共20分)?三、简答题(共30分)?四、计算题(共30分) works and the 2 Application 3 Transport work 5 The link layer and local works复****方法要领?基本概念:网络模型层次、协议?基本术语:如TCP/IP LAN WAN DNS?基本计算:如分片、帧长、CRC等?复****提纲:书本上内容的浓缩?课后作业Chapter 1: IntroductionOur goal:?get “feel” and terminology?more depth, detail laterin course?approach:?use as exampleOverview:?what’s the ??network edge; hosts, , physical work core: packet/circuit switching, structure?performance: loss, delay, throughput?protocol layers, service works Under Attack?historyWhat’s a work protocol?munication activity in governed by protocolsProtocol Elements?Syntax (语法)?Semantics(语义)?Timing(时序关系)?Actions(动作)protocols define(P35):?format, order of messages sent and received work entities, and actions taken on the transmission/receiptof amessage A closer look work structure:?network edge:?applications and work core:?work works网络的网络?works, physical media: communication links接入网络,work work work edge:由所有连接在因特网上的主机组成。这部分是用户直接使用的,用来进行通信(传送数据、音频或视频)work core:由大量网络链路和连接这些网络的路由器组成。这部分是为边缘部分提供服务的(提供连通性和交换)。 Physical Media?Bit: propagates between transmitter/rcvr pairs?位:在发送和接收对间传输?physical link: what lies between transmitter & receiver?guided media:导向的传输媒体?signals propagate in solid media: copper, fiber, coax?unguided media:非导向(无线)?signals propagate freely, ., radio