Layer Summary L Task Unit Peer By 5

Layer Summary L Task Unit Peer @ By @ 5 Tell peer what Message application needs Destination Application Host only 4 ETE control of data transfer Segment Destination OS Host only 3 Route data thru Network Datagram All nodes along path OS All nodes 2 Delimit packet; Link xfer control Frame Neighbor node NIC All nodes 1 Transfer bits over link Bit Neighbor node NIC All nodes Ch. 1: Summary 1/3

Layer Issues & details L Types Ex. Node 5 1. User oriented 2. Infrastructure 1. http, ftp 2. Dns Applicat’n gateway 4 1. Reliable 2. Best effort 1. TCP 2. UDP 3 1. Circuit Sw. 2. Packet Sw. 1. Phone 2. tcp/ip Router Rtg algo. , address, forwarding rules 2 1. PTP protocol 2. LAN protocol 1. hdlc, ppp 2. ethernet Bridge L 2 -switch Delimitation 1. filler, 2. MAC 1 1. PTP link 2. shared link Repeater Hub Cable spec/ bit coding /clock sync Ch. 1: Summary Defines Interaction rules, message semantic and format Appl. proc. multiplex error/flow/cong ctrl 2/3

Chapter 1 Contents General introduction n Introduction to Layers & Protocols n Layering of the mail service n The 5 layers: motivation & basics n What is a protocol n OSI and Internet layer models n Layer model usage & Encapsulation n Design issues of each layer n Extra slides Chapter Summary: This file n Ch. 1: Summary 1 -18 19 -26 27 -31 32 -40 41 -42 43 -47 48 -53 54 -61 62 -80 1 -3 3/3