15-441 Computer Networking ecture 16-Transport Protocols
15-441 Computer Networking Lecture 16 – Transport Protocols
Announcements Mid-semester grades Based on project 1+ midterm HW1+ HW2 42.5% of class If you got a D+, D, D-or F must meet with Dave or me Much of class grade remains! Discussion about the midterm next time One or two people still haven't taken it Lecture 16: Transport Protocols
2 Lecture 16: Transport Protocols Announcements • Mid-semester grades • Based on project1 + midterm + HW1 + HW2 • 42.5% of class • If you got a D+,D, D- or F → must meet with Dave or me • Much of class grade remains! • Discussion about the midterm next time • One or two people still haven’t taken it
Outline Transport introduction Error recovery flow control Lecture 16: Transport Protocols
3 Lecture 16: Transport Protocols Outline • Transport introduction • Error recovery & flow control
Transport protocols Lowest level end-to- end protocol Header generated by 7 7 sender is interpreted 6 6 only by the destination 5 Routers view transport header as part of the Transport Transport payload P P P Datalink 2 2 Datalink Physical Physical router Lecture 16: Transport Protocols
4 Lecture 16: Transport Protocols Transport Protocols • Lowest level end-toend protocol. • Header generated by sender is interpreted only by the destination • Routers view transport header as part of the payload 7 6 5 7 6 5 Transport IP Datalink Physical Transport IP Datalink Physical IP router 2 2 1 1
Functionality Split Network provides best-effort delivery End-systems implement many functions Reliability n-order delIvery · Demultiplexing Message boundaries Connection abstraction ° Congestion control Lecture 16: Transport Protocols
5 Lecture 16: Transport Protocols Functionality Split • Network provides best-effort delivery • End-systems implement many functions • Reliability • In-order delivery • Demultiplexing • Message boundaries • Connection abstraction • Congestion control • …