Chapter 4 Network Layer computer networking 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!) f 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 note our copyright of this material. Addison-Wesley,July 2004. Thanks and enjoy!JFK/KWR All material copyright 1996-2006 J.F Kurose and K.W.Ross,All Rights Reserved Network Layer 4-1
Network Layer 4-1 Chapter 4 Network Layer 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: ❑ 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!) ❑ 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 4:Network Layer Chapter goals: Ounderstand principles behind network layer services: o network layer service models o forwarding versus routing o how a router works o routing (path selection) o dealing with scale o advanced topics:IPv6,mobility instantiation,implementation in the Internet Network Layer 4-2
Network Layer 4-2 Chapter 4: Network Layer Chapter goals: understand principles behind network layer services: network layer service models forwarding versus routing how a router works routing (path selection) dealing with scale advanced topics: IPv6, mobility instantiation, implementation in the Internet
Chapter 4:Network Layer ▣4.1 Introduction 4.5 Routing algorithms 4.2 Virtual circuit and o Link state datagram networks o Distance Vector ▣4.3What's inside a o Hierarchical routing router 4.6 Routing in the 4.4 IP:Internet Internet Protocol O RIP o OSPF o Datagram format o IPv4 addressing oBGP ICMP ▣4.7 Broadcast and IPv6 multicast routing Network Layer 4-3
Network Layer 4-3 Chapter 4: Network Layer 4. 1 Introduction 4.2 Virtual circuit and datagram networks 4.3 What’s inside a router 4.4 IP: Internet Protocol Datagram format IPv4 addressing ICMP IPv6 4.5 Routing algorithms Link state Distance Vector Hierarchical routing 4.6 Routing in the Internet RIP OSPF BGP 4.7 Broadcast and multicast routing
Network layer transport segment from sending to receiving host applicatior TransporT ▣on sending side network data link physical network encapsulates segments network data link network data link physical data link physical physical into datagrams network data link on rcving side,delivers physical network data link segments to transport physical network layer network data link data link physical physical network layer protocols network data link application in every host,router physical transport network data link Router examines header physical fields in all IP datagrams passing through it Network Layer 4-4
Network Layer 4-4 Network layer transport segment from sending to receiving host on sending side encapsulates segments into datagrams on rcving side, delivers segments to transport layer network layer protocols in every host, router Router examines header fields in all IP datagrams passing through it network data link physical network data link physical network data link physical network data link physical network data link physical network data link physical network data link physical network data link physical application transport network data link physical application transport network data link physical
Two Key Network-Layer Functions ▣forwarding:.move analogy: packets from router's input to appropriate ▣routing:process of router output planning trip from source to dest ▣routing:determine route taken by forwarding:process packets from source of getting through to dest. single interchange o routing algorithms Network Layer 4-5
Network Layer 4-5 Two Key Network-Layer Functions forwarding: move packets from router’s input to appropriate router output routing: determine route taken by packets from source to dest. routing algorithms analogy: routing: process of planning trip from source to dest forwarding: process of getting through single interchange