TAILIEUCHUNG - The Illustrated Network- P34

The Illustrated Network- P34:In this chapter, you will learn about the protocol stack used on the global public Internet and how these protocols have been evolving in today’s world. We’ll review some key basic defi nitions and see the network used to illustrate all of the examples in this book, as well as the packet content, the role that hosts and routers play on the network, and how graphic user and command line interfaces (GUI and CLI, respectively) both are used to interact with devices. | 299 QUESTIONS FOR READERS Figure shows some of the concepts discussed in this chapter and can be used to help you answer the following questions. H e a d e r 1 byte 1 byte 1 byte 1 byte Source Port Destination Port Sequence Number Acknowledgment Number Header RESV i RESV Length Control Bits Window Size TCP Checksum Urgent Pointer Options Field variable length maximum 40 bytes 0 padded to 4-byte multiple r DATA application message wincli2 FTP Handshake Using 1460-byte Segments Active OPEN SYN SEQ ISN .72d1 WIN 65535 Client port 2790 MSS OPT 1460 bsdserver Passive OPEN SYN SEQ ISN .e33a WIN 57344 ----------------------------------- OPEN MSS OPT 1460 OPEN ACK WIN 65535 3-Way Handshake Complete FIGURE The TCP header fields and three-way handshake example. 1. What are the three phases of connection-oriented communications 2. Which fields are present in the TCP header but absent in UDP Why are they not needed in UDP 3. What is the TCP flow control mechanism called 4. What does it mean when the initial sequence and acknowledgment numbers are relative 5. What is the silly window syndrome What is the Nagle algorithm CHAPTER Multiplexing and Sockets 12 What You Will Learn In this chapter you will learn about how multiplexing and demultiplexing and sockets are used in TCP IP. We ll see how multiplexing allows many applications can share a single TCP IP stock process. You will learn how layer and applications interact to make multiplexing and the socket concept very helpful in networking. We ll use a small utility program to investigate sockets and illustrate the concepts in this chapter. Now that we ve looked at UDP and TCP in detail this chapter explores two key concepts that make understanding how UDP and TCP work much easier multiplexing and sockets. Technically the term should be multiplexing and demultiplexing but because mixing things together makes little sense unless you can get them back again most people just say multiplexing and let

Đã phát hiện trình chặn quảng cáo AdBlock
Trang web này phụ thuộc vào doanh thu từ số lần hiển thị quảng cáo để tồn tại. Vui lòng tắt trình chặn quảng cáo của bạn hoặc tạm dừng tính năng chặn quảng cáo cho trang web này.