计算机网络课件英文版Chapter3_Transport Layer.ppt

Transport Layer 3-1 Chapter 3 Transport working: A Top Down Approach 4 th edition. Jim Kurose, Keith Ross Addison-Wesley, July 2007. 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 (., 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 , 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 1996-2007 Kurose and . Ross, All Rights Reserved Transport Layer 3-2 Chapter 3: Transport Layer Our goals: r understand principles behind transport layer services: m multiplexing/demultipl exing m reliable data transfer m flow control m congestion control r learn about transport layer protocols in the : m UDP: connectionless transport m TCP: connection-oriented transport m TCP congestion control Transport Layer 3-3 Chapter 3 outline r Transport-layer services r Multiplexing and demultiplexing r Connectionless transport: UDP r Principles of reliable data transfer r Connection-oriented transport: TCP m segment structure m reliable data transfer m flow control m connection management r Principles of congestion control r TCP congestion control Transport Layer 3-5 Transport vs. network layer work layer: logical communication between hosts r transport layer: logical communication between processes m relies on, enhances, network layer services Household analogy: 12 kids sending letters to 12 kids r processes = kids r app messages = letters in e