CSE 127 Lecture Notes - Lecture 15: User Datagram Protocol, Internet Control Message Protocol, Internet Protocol Suite

• School: UCSD
• Department: Computer Science and Engineering
• Course: CSE 127
• Professor: Savage, Stefan

Document Summary

Physical layer: transmission of raw bits over a physical data link connecting network nodes. Link layer: transmission of data frames within a local network (without intervening routers) Internet layer (ip): fragmentation, reassembly, and end-to-end (across network boundaries) Uniform interface that hides the underlying network topology. Transport layer: port-addressed host-to-host communications (on lan or wan) User datagram protocol (udp): single packet transmission w/ no reliability or ordering mechanisms. Transmission control protocol (tcp): connection establishment, reliable transmission, and flow-control. Note: each layer down has an extra piece of metadata to know how to interpret the data. Network topology: host a router router router b. Talk to a local dns server that will resolve the name to an ip address! Assign sequence numbers to indicate which packets you"ve gotten. Address each packet so it can traverse network and arrive at host. So it knows who to send a reply. Shortest paths works within organizationsas soon as you send across orgs, they become.