Wireshark DNS实验—Wireshark Lab: DNS v7.0(计算机网络自顶向下第七版)

Posted 2022-11-25 之墨_

Wireshark Lab: DNS v7.0

1

Run nslookup to obtain the IP address of a Web server in Asia. What is the IP address of that server?

$IPaddress$有
$$\begin{gathered} \mathrm{47.101.174.127} \\ \mathrm{119.3.65.116} \\ \mathrm{8.134.64.214} \\ \mathrm{120.92.83.126} \\ \mathrm{139.159.246.60} \end{gathered}$$

2

Run nslookup to determine the authoritative DNS servers for a university in Europe.

伦敦大学的权威$DNS$服务器。

3

Run nslookup so that one of the DNS servers obtained in Question 2 is queried for the mail servers for Yahoo! mail. What is its IP address?

通过伦敦大学的$DNS$无法找到$Yahoomail$

通过中国科大$DNS$服务器找到其$IP$如下图所示

$ipconfig$各指令如下图

ipconfig /all

ipconfig /displaydns

ipconfig /flushdns

4

Locate the DNS query and response messages. Are then sent over UDP or TCP?

​ 通过$UDP$传输。

5

What is the destination port for the DNS query message? What is the source port of DNS response message?

端口号都是$53$。

6

To what IP address is the DNS query message sent? Use ipconfig to determine the IP address of your local DNS server. Are these two IP addresses the same?

$IP$地址为$\mathrm{202.38.64.17}$，与本地$DNS$服务器$IP$地址相同。

7

Examine the DNS query message. What “Type” of DNS query is it? Does the query message contain any “answers”?

类型为$AAAA$，不包含$“answers"$。

8

Examine the DNS response message. How many “answers” are provided? What do each of these answers contain?

有 $3$个$“answer”$，包含$name,type,class\dots cname,address$等信息。

9

Consider the subsequent TCP SYN packet sent by your host. Does the destination IP address of the SYN packet correspond to any of the IP addresses provided in the DNS response message?

在$responsemessage$中的$answer$找到对应的$IP$地址。

10

This web page contains images. Before retrieving each image, does your host issue new DNS queries?

没有发起新的请求。

11

What is the destination port for the DNS query message? What is the source port of DNS response message?

都是$53$号端口。

12

To what IP address is the DNS query message sent? Is this the IP address of your default local DNS server?

目的$IP$地址与本地$DNS$服务器的$IP$地址相同。

13

Examine the DNS query message. What “Type” of DNS query is it? Does the query message contain any “answers”?

类型为$A$，不包含$answers$。

14

Examine the DNS response message. How many “answers” are provided? What do each of these answers contain?

有$3$个$answer$，每个$answer$包含$name,type,class,timetolive,datalength,cname,address$等消息

15

Provide a screenshot

16

To what IP address is the DNS query message sent? Is this the IP address of your default local DNS server?

目标$IP$地址为$\mathrm{202.38.64.56}$，是我的本地$DNS$服务器$IP$。

17

Examine the DNS query message. What “Type” of DNS query is it? Does the query message contain any “answers”?

类型为$NS$，不包含$answers$。

18

Examine the DNS response message. What MIT nameservers does the response message provide? Does this response message also provide the IP addresses of the MIT namesers?

提供一个$Authoritativenameserver$ $dscb.akamaiedge.net$，没有提供$IP$地址。

19

Provide a screenshot.

20

what IP address is the DNS query message sent? Is this the IP address of your default local DNS server? If not, what does the IP address correspond to?

超时，故用$ns.ustc.edu.cn$进行请求。$DNS$请求发送的$IP$地址为$2001:da8:d800::56$，与科大服务器$IP$一致。

21

Examine the DNS query message. What “Type” of DNS query is it? Does the query message contain any “answers”?

存在两个类型的查询请求，分别是$A，AAAA$类型，都不包含$answer$。

22

Examine the DNS response message. How many “answers” are provided? What does each of these answers contain?

只有$1$个$answer$，包含$name,type,class,timetolive,adtalength,address$等信息。

23

Provide a screenshot.