What's the Internet:"nuts and bolts"view X protocols control sending, router 珍 workstation receiving of msgs 目server 区 e.g.,TCP,IP,HTTP,FTP,PPP mobile Internet:"network of eal ISP networks" Loosely(宽松的)hierarchical public Internet versus private intranet(内联网) ▣Internet standards RFC:Request for comments IETF:Internet Engineering Task Force(因特网工程任务组) company network Introduction 1-6
Introduction 1-6 What’s the Internet: “nuts and bolts” view ❑ protocols control sending, receiving of msgs ❖ e.g., TCP, IP, HTTP, FTP, PPP ❑ Internet: “network of networks” ❖ Loosely（宽松的） hierarchical ❖ public Internet versus private intranet（内联网） ❑ Internet standards ❖ RFC: Request for comments ❖ IETF: Internet Engineering Task Force（因特网工程任务组） local ISP company network regional ISP router workstation server mobile
What's the Internet:a service view ▣communication infrastructure(下部胸造) enables distributed(分布式的) 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 ❑ communication infrastructure （下部构造） enables distributed（分布式的） applications: ❖ Web, email, games, ecommerce, file sharing ❑ communication services provided to apps: ❖ Connectionless unreliable ❖ connection-oriented reliable
What's a protocol? human protocols: network protocols: ▣"what's the time?" ▣machines rather than 口"I have a question" humans ▣introductions ▣all communication activity in Internet .specific msgs sent governed by protocols specific actions taken protocols define format, when msgs received, order of msgs sent and or other events received among network entities,and actions taken on msg transmission,receipt Introduction 1-8
Introduction 1-8 What’s a protocol? human protocols: ❑ “what’s the time?” ❑ “I have a question” ❑ introductions . specific msgs sent . specific actions taken when msgs received, or other events network protocols: ❑ machines rather than humans ❑ all communication activity in Internet governed by protocols protocols define format, order of msgs sent and received among network entities, and actions taken on msg transmission, receipt
What's a protocol? a human protocol and a computer network protocol: Hi ICP connection Hi request TCP connection Got the response time? Get http://www.awl.com/kurose-ross ★-2：00 kfile> time Q:Other human protocols? Introduction 1-9
Introduction 1-9 What’s a protocol? a human protocol and a computer network protocol: Q: Other human protocols? Hi Hi Got the time? 2:00 TCP connection request TCP connection response Get http://www.awl.com/kurose-ross <file> time
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 1-10
Introduction 1-10 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