3rdEditionChapter1_june21.ppt

Chapter 1: Introduction Our goal: get “feel” and terminology more depth, detail later in course approach: use Internet as example Overview: what’s the Internet what’s a protocol? network edge network core access net, physical media Internet/ISP structure performance: loss, delay protocol layers, service models 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 What’s the Internet: “nuts and bolts” view millions of connected computing devices: hosts = end systems running network apps communication links fiber, copper, radio, satellite transmission rate(bit/s) = bandwidth routers: forward packets (chunks of data) What’s the Internet: “nuts and bolts” view Internet: “network of networks” loosely hierarchical public Internet versus private intranet protocols control sending, receiving of msgs e.g., TCP, IP, HTTP, FTP, PPP Internet standards IETF: Internet Engineering Task Force RFC: Request for comments(5000) IEEE 802 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 What’s a protocol? a human protocol and a computer network protocol: What’s a protocol? Protocol is the most important content! 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 A closer look at network structure: network edge: applications and hosts network core: routers network of networks access networks, physical media: communication links Chapter 1: roadmap 1.1 What is the Inter