NAME: 孙浩

ID:2024141530052

# 一. The Basic HTTP GET/response interaction

# 1.Is your browser running HTTP version 1.0 or 1.1? What version of HTTP is the server running?

HTTP 版本是 1.1；HTTP 版本是 1.1

# 2.What languages (if any) does your browser indicate that it can accept to the server?

Zh-CN 中文

# 3.What is the IP address of your computer? Of the gaia.cs.umass.edu server?

我的 IP 是 10.193.239.245；服务器 IP 是 128.119.245.12

# 4.What is the status code returned from the server to your browser?

200 OK

# 5.When was the HTML file that you are retrieving last modified at the server?

最后修改是在 Tue,28 Oct 2025 05:59:01 GMT

# 6.How many bytes of content are being returned to your browser?

128bytes

# 7.By inspecting the raw data in the packet content window, do you see any headers within the data that are not displayed in the packet-listing window? If so, name one.

有的，比如说 ETag

# 二.The HTTP CONDITIONAL GET/response interaction

# 8.Inspect the contents of the first HTTP GET request from your browser to the server. Do you see an “IF-MODIFIED-SINCE” line in the HTTP GET?

没有看到 IF-MODIFIED-SINCE

# 9.Inspect the contents of the server response. Did the server explicitly return the contents of the file? How can you tell?

可以直接看到返回的文件内容

# 10.Now inspect the contents of the second HTTP GET request from your browser to the server. Do you see an “IF-MODIFIED-SINCE:” line in the HTTP GET? If so, what information follows the “IF-MODIFIED-SINCE:” header?

可以看到 “IF-MODIFIED-SINCE:”，内容为 Tue, 28 Oct 2025 05:59:01 GMT

# 11.What is the HTTP status code and phrase returned from the server in response to this second HTTP GET? Did the server explicitly return the contents of the file? Explain.

返回 304 Not Modified, 没有明确返回文件内容，304 说明文件没有被修改，客户端可以使用本地缓存，无法看到文件内容

# 三. Retrieving Long Documents

# 12.How many HTTP GET request messages did your browser send? Which packet number in the trace contains the GET message for the Bill or Rights?

有两个 GET 请求包，对于权利法案的包在 NO.500

# 13.Which packet number in the trace contains the status code and phrase associated with the response to the HTTP GET request?

状态码和包号在 NO.541

# 14.What is the status code and phrase in the response?

状态码是 200 OK

# 15.How many data-containing TCP segments were needed to carry the single HTTP response and the text of the Bill of Rights?

使用了四个包含数据的 TCP 段承载

# 四、HTML Documents with Embedded Objects

# 16.How many HTTP GET request messages did your browser send? To which Internet addresses were these GET requests sent?

有三个 GET 请求，

128.119.245.12；165.193.123.218;134.241.6.82

# 17.Can you tell whether your browser downloaded the two images serially, or whether they were downloaded from the two web sites in parallel? Explain.

是同时从两个网站下载的，通过分析它们的时间可以看到，pearson.png 的 GET 请求在 7.305485 秒时发送，另一张图片的请求在 7.308803 秒时发送。我们可以看到，后面图片的请求是在前一张图片的响应完全接收之前就发送的。

# 五、HTTP Authentication

# 18.What is the server’s response (status code and phrase) in response to the initial HTTP GET message from your browser?

状态码是 401 Unauthorized

# 19.When your browser’s sends the HTTP GET message for the second time, what new field is included in the HTTP GET message?

HTTP 头中包含了一个 Authorization 的字段，值为

Basic ZXRoLXN0dWRlbnRzOm5ldHdvcmtz