上海交通大学：《计算机通讯与网络》教学资源（PPT课件）Chapter 1 roadmap

Chapter 1 Introduction computer A TOT-DOWN APPROACH networking third edition James F.Kurose Keith W.Ross A note on the use of these ppt slides: We're making these slides freely available to all(faculty,students,readers). They're in PowerPoint form so you can add,modify,and delete slides Computer Networking: (including this one)and slide content to suit your needs.They obviously A Top Down Approach represent a lot of work on our part.In return for use,we only ask the following: Featuring the Internet, If you use these slides(e.g.,in a class)in substantially unaltered form, 3rd edition. that you mention their source (after all,we'd like people to use our book!) If you post any slides in substantially unaltered form on a ww site,that Jim Kurose,Keith Ross you note that they are adapted from(or perhaps identical to)our slides,and Addison-Wesley,July note our copyright of this material. 2004. Thanks and enjoy!JFK/KWR All material copyright 1996-2006 J.F Kurose and K.W.Ross,All Rights Reserved Introduction 1-1

Introduction 1-1 Chapter 1 Introduction Computer Networking: A Top Down Approach Featuring the Internet, 3rd edition. Jim Kurose, Keith Ross Addison-Wesley, July 2004. A note on the use of these ppt slides: We’re making these slides freely available to all (faculty, students, readers). They’re in PowerPoint form so you can add, modify, and delete slides (including this one) and slide content to suit your needs. They obviously represent a lot of work on our part. In return for use, we only ask the following: q If you use these slides (e.g., in a class) in substantially unaltered form, that you mention their source (after all, we’d like people to use our book!) q If you post any slides in substantially unaltered form on a www site, that you note that they are adapted from (or perhaps identical to) our slides, and note our copyright of this material. Thanks and enjoy! JFK/KWR All material copyright 1996-2006 J.F Kurose and K.W. Ross, All Rights Reserved

Chapter 1:Introduction Our goal: Overview: 0 get "feel"and ▣what's the Internet terminology 口what's a protocol?? more depth,detail □network edge later in course ▣network core 口approach: access net,physical media use Internet as Internet/ISP structure example performance:loss,delay protocol layers,service models network modeling Introduction 1-2

Introduction 1-2 Chapter 1: Introduction Our goal: q get “feel” and terminology q more depth, detail later in course q approach: v use Internet as example Overview: q what’s the Internet q what’s a protocol? q network edge q network core q access net, physical media q Internet/ISP structure q performance: loss, delay q protocol layers, service models q network modeling

Chapter 1:roadmap 1.1 What is the Internet? 1.2 Network edge 1.3 Network core 1.4 Network access and physical media 1.5 Internet structure and ISPs 1.6 Delay loss in packet-switched networks 1.7 Protocol layers,service models 1.8 History Introduction 1-3

Introduction 1-3 Chapter 1: roadmap 1.1 What is the Internet? 1.2 Network edge 1.3 Network core 1.4 Network access and physical media 1.5 Internet structure and ISPs 1.6 Delay & loss in packet-switched networks 1.7 Protocol layers, service models 1.8 History

What's the Internet:"nuts and bolts"view millions of connected router computing devices:hosts workstation end systems 目server mobile running network apps ocal ISP communication links fiber,copper,radio, satellite … transmission rate bandwidth 口 routers:forward packets (chunks of data) company (CD network Introduction 1-4

Introduction 1-4 What’s the Internet: “nuts and bolts” view q millions of connected computing devices: hosts = end systems q running network apps q communication links v fiber, copper, radio, satellite v transmission rate = bandwidth q routers: forward packets (chunks of data) local ISP company network regional ISP router workstation server mobile

"Cool"internet appliances Web-enabled toaster weather forecaster IP picture frame http://www.ceiva.com/ World's smallest web server http://www-ccs.cs.umass.edu/~shri/iPic.html Internet phones Introduction 1-5

Introduction 1-5 “Cool” internet appliances World’s smallest web server http://www-ccs.cs.umass.edu/~shri/iPic.html IP picture frame http://www.ceiva.com/ Web-enabled toaster + weather forecaster Internet phones

What's the Internet:"nuts and bolts"view protocols control sending, router workstation receiving of msgs 目server e.g.,TCP,IP,HTTP,FTP PPP mobile Internet:"network of networks" loosely hierarchical public Internet versus regionaSP private intranet ▣Internet standards RFC:Reguest for comments IETF:Internet Engineering Task Force company network Introduction 1-6

Introduction 1-6 What’s the Internet: “nuts and bolts” view q protocols control sending, receiving of msgs v e.g., TCP, IP, HTTP, FTP, PPP q Internet: “network of networks” v loosely hierarchical v public Internet versus private intranet q Internet standards v RFC: Request for comments v IETF: Internet Engineering Task Force local ISP company network regional ISP router workstation server mobile

What's the Internet:a service view communication infrastructure enables distributed applications: ÷Web,email,,games,e- commerce,file sharing communication services provided to apps: *Connectionless unreliable *connection-oriented reliable Introduction 1-7

Introduction 1-7 What’s the Internet: a service view q communication infrastructure enables distributed applications: v Web, email, games, e- commerce, file sharing q communication services provided to apps: v Connectionless unreliable v connection-oriented reliable

Wikipedia:The Internet The Internet is a global system of interconnected computer networks that use the standard Internet Protocol Suite (TCP/IP)to serve billions of users worldwide.It is a network of networks that consists of millions of private and public,academic,business, and government networks of local to global scope that are linked by a broad array of electronic and optical networking technologies.The Internet carries a vast array of information resources and services, most notably the inter-linked hypertext documents of the World Wide Web(W)and the infrastructure to support electronic mail. Introduction 1-8

Introduction 1-8 Wikipedia: The Internet q The Internet is a global system of interconnected computer networks that use the standard Internet Protocol Suite (TCP/IP) to serve billions of users worldwide. It is a network of networks that consists of millions of private and public, academic, business, and government networks of local to global scope that are linked by a broad array of electronic and optical networking technologies. The Internet carries a vast array of information resources and services, most notably the inter-linked hypertext documents of the World Wide Web (WWW) and the infrastructure to support electronic mail

Wikipedia:The Internet Most traditional communications media,such as telephone and television services,are reshaped or redefined using the technologies of the Internet,giving rise to services such as Voice over Internet Protocol (VolP)and IPTV. Newspaper publishing has been reshaped into Web sites,blogging,and web feeds.The Internet has enabled or accelerated the creation of new forms of human interactions through instant messaging,Internet forums, and social networking sites. Introduction 1-9

Introduction 1-9 Wikipedia: The Internet q Most traditional communications media, such as telephone and television services, are reshaped or redefined using the technologies of the Internet, giving rise to services such as Voice over Internet Protocol (VoIP) and IPTV. Newspaper publishing has been reshaped into Web sites, blogging, and web feeds. The Internet has enabled or accelerated the creation of new forms of human interactions through instant messaging, Internet forums, and social networking sites

Wikipedia:The Internet The origins of the Internet reach back to the 1960s when the United States funded research projects of its military agencies to build robust,fault-tolerant and distributed computer networks.This research and a period of civilian funding of a new U.S.backbone by the National Science Foundation spawned worldwide participation in the development of new networking technologies and led to the commercialization of an international network in the mid 1990s,and resulted in the following popularization of countless applications in virtually every aspect of modern human life.As of 2009,an estimated quarter of Earth's population uses the services of the Internet. Introduction 1-10

Introduction 1-10 Wikipedia: The Internet q The origins of the Internet reach back to the 1960s when the United States funded research projects of its military agencies to build robust, fault-tolerant and distributed computer networks. This research and a period of civilian funding of a new U.S. backbone by the National Science Foundation spawned worldwide participation in the development of new networking technologies and led to the commercialization of an international network in the mid 1990s, and resulted in the following popularization of countless applications in virtually every aspect of modern human life. As of 2009, an estimated quarter of Earth's population uses the services of the Internet