Outlines requirements and time allocation (通过人类用语言交流信息的情况，重点讨论网络交换信息必须采用的各种协议，用 讨论式教学方式教学。) 12 The network Edge(网络边缘) 1.2.1 End System,Clients,and Servers 20分钟 Millions of connected computing devices:hosts,end-systems pe's workstations,servers PDA's phones,toasters running network apps 10分钟 Communication links fiber copper,ado,satellite routers:forward packets(chunks)of data thru network 1.2.2 Connectionless and Connection-Oriented Services 20分钟 Connection-oriented service Goal:data transfer between end sys. Handshaking:stup (prepare for)head ofme TCP-Transmission Control Protoco Internet's connection-oriented service 10分钟 Connectionless service Goal:data transfer between end systems UDP-User Datagram Protocol [RFC 768]:Intemet's connectionless service unreliable datatransfer no flow control no congestion control 20分钟 App's using TCP HTIP (WWW).FTP (file transfer),Telnet (remote login).SMTP (email) App's using UDP: treaming media,teleconferencing.Intemet telephony (重点讲解网络提供的两种连接服务，用讨论式教学方式教学。) 复习本次课的主要内容。 10分钟2 Outlines, requirements and time allocation （通过人类用语言交流信息的情况，重点讨论网络交换信息必须采用的各种协议，用 讨论式教学方式教学。） 1.2 The network Edge（网络边缘） 1.2.1 End System, Clients, and Servers Millions of connected computing devices: hosts, end-systems pc’s workstations, servers PDA’s phones, toasters running network apps Communication links fiber, copper, radio, satellite routers: forward packets (chunks) of data thru network 1.2.2 Connectionless and Connection-Oriented Services Connection-oriented service Goal: data transfer between end sys. Handshaking: setup (prepare for) data transfer ahead of time TCP - Transmission Control Protocol Internet’s connection-oriented service Connectionless service Goal: data transfer between end systems UDP - User Datagram Protocol [RFC 768]: Internet’s connectionless service unreliable data transfer no flow control no congestion control App’s using TCP: HTTP (WWW), FTP (file transfer), Telnet (remote login), SMTP (email) App’s using UDP: streaming media, teleconferencing, Internet telephony （重点讲解网络提供的两种连接服务，用讨论式教学方式教学。） 复习本次课的主要内容。 20 分钟 10 分钟 20 分钟 10 分钟 20 分钟 10 分钟