使用的资料

计算机网络自顶向下方法 第7版

实验手册

参考前人第六版资料

Wireshark-win64-3.4.2

操作系统：Windows 7

实验步骤

To begin packet capture, select the Capture pull down menu and select Interfaces. This will cause the “Wireshark: Capture Interfaces” window to be displayed, as shown in Figure 4.

步骤3，打开捕获窗口，选择选项，选择一个接口。

也可以在欢迎界面直接选取。

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While Wireshark is running, enter the URL:
http://gaia.cs.umass.edu/wireshark-labs/INTRO-wireshark-file1.html
and have that page displayed in your browser. In order to display this page, your browser will contact the HTTP server at gaia.cs.umass.edu and exchange HTTP messages with the server in order to download this page, as discussed in section 2.2 of the text. The Ethernet frames containing these HTTP messages (as well as all other frames passing through your Ethernet adapter) will be captured by Wireshark.

步骤6，捕获网站的HTTP信息。停止捕获，选择http进行观察。

因为我之前已经访问过了一次，因此提示：304 Not Modified，在书的2.2.6小结中有具体说明。

如果使用的是“代理”proxy，Host部分显示的是代理服务器的地址。

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考察点

What to hand in The goal of this first lab was primarily to introduce you to Wireshark. The following questions will demonstrate that you’ve been able to get Wireshark up and running, and have explored some of its capabilities. Answer the following questions, based on your Wireshark experimentation:

  1. List 3 different protocols that appear in the protocol column in the unfiltered packet-listing window in step 7 above.

列取三种协议，有很多，第一页中有常见的TCP。

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  1. How long did it take from when the HTTP GET message was sent until the HTTP OK reply was received? (By default, the value of the Time column in the packet-listing window is the amount of time, in seconds, since Wireshark tracing began. To display the Time field in time-of-day format, select the Wireshark View pull down menu, then select Time Display Format, then select Time-of-day.)

在视图中选择时间显示格式，计算时间差。

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  1. What is the Internet address of the gaia.cs.umass.edu (also known as www-net.cs.umass.edu)? What is the Internet address of your computer?

可以观察IP协议，判断源地址和目的地址。

也可以通过步骤6中的Source和Destination来进行观察。

因为我开了许多网页，有其他不相关的HTTP信息，可以看后面的Info进行区分。

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  1. Print the two HTTP messages (GET and OK) referred to in question 2 above. To do so, select Print from the Wireshark File command menu, and select the “Selected Packet Only” and “Print as displayed” radial buttons, and then click OK.

总结

本次实验是HTTP相关的，涉及一些第二章应用层的部分，有些看书过程中的小细节在实验中展现出来，很惊喜。