Shulou(Shulou.com)05/31 Report--

Hello everyone, Lin Fei to answer the above questions, how to set up dns, many people do not know dns, now let's take a look!

1. Since entering the Internet era, everyone's life has become more colorful, but there are also a lot of troubles. For example, there are large groups of rubbish and abyss in the information ocean from time to time, which is difficult to prevent. What I am talking about here is the inexplicable jump of the web page in the process of surfing the Internet. A good web page suddenly turns into a full-screen ad. Or the page that could have been accessed normally suddenly cannot be opened, but software such as QQ can log in normally. In fact, these disturbing anomalies mean that you may be the victim of DNS hijacking and poisoning. What if dns is hijacked?

2. What exactly is DNS?

Although we often surf the Internet, not everyone knows the mechanism behind opening web pages. At the click of the mouse, the web page appears in front of you. How familiar, but behind this familiar operation, there is a set of interlocking processes. From the time the user clicks the mouse and presses the enter key to display the web page, the information will be sent through the browser, then transmitted through the route, and then the domain name will be resolved into IP by DNS. When the server is found, the server sends the content to the user, then the data is forwarded by the route, and finally the content is presented to the user by the browser. According to the actual situation, there may be more barriers in this process, such as firewalls, proxy servers and so on.

4. What if dns is hijacked?

5. There are many links to browse the web, and there are also many opportunities to be hijacked, among which DNS is very easy to be tampered with.

6. In this process, there is a traitor in any link, such as browser, routing, DNS, server and so on. It may cause the web page to be inaccessible. And DNS is probably the one that has been tampered with the most. The full name of DNS is the domain name system, which plays the role of resolving domain names into IP addresses. We can access the website by connecting to the IP address of the server of the website. The role of DNS here is to parse "www.baidu.com" into an IP address similar to "123.125.114.144", so that you can connect to the server at this address to access the website.

7. What if dns is hijacked?

8. Parsing URL to IP address is the role that DNS plays.

9. In the process of surfing the Internet, there are too many reasons that can affect DNS, such as your PC settings, router settings, operator settings and so on. Once there is an error in DNS, the domain name cannot be resolved to the correct IP address, and naturally we will not be able to access the correct page. So if you find that you can't open a web page, but web software like QQ that connects directly to IP can work properly, then DNS is a very doubtful reason.

What happens if something goes wrong with DNS?

11. This part of DNS will be affected by many reasons, so many stakeholders will play tricks on it. For example, DNS hijacking is a very common advertising tool.

12. If the DNS server is not specifically set up, the DNS server will be provided by the operator. In theory, you should use the DNS server provided by the operator to provide you with the correct IP hop count, but many operators' DNS servers are ugly. You can often see operators jump you to pages such as Internet packages, and even get redirected to competitor B when you enter the A shopping network, which is called DNS hijacking.

13. After opening Baidu, the whole web page is forced to jump to XX Casino, which is a typical DNS hijacking.

14. To deal with DNS hijacking by operators, setting up a reliable DNS server can often solve the problem. But after setting up a reliable DNS server, many friends are still unable to resolve the correct IP address. For example, the IP address of a website can be Ping, but cannot be accessed. This situation is usually caused by DNS pollution.

15. Although the DNS server works properly, when we send a domain name resolution request to the DNS server, it is sent through a UDP connection. UDP is not a reliable connection. Domain name resolution requests can be intercepted halfway and then send you the wrong IP address by pretending to be a DNS server. The IP address is incorrect. Naturally, it is impossible to visit the website normally. We may see ads, phishing pages, or nothing.

What if dns is hijacked?

17. DNS uses UDP connection by default, and it is not encrypted, so it is easy to be contaminated.

In any case, a DNS error means that you cannot access the site correctly. In the whole process of surfing the Internet, DNS is undoubtedly fragile and not controlled by users. If someone wants to use DNS to harm you, there is nothing ordinary people can do about it. So is there any way to keep DNS from making frequent mistakes?

Is there any way to save the DNS error?

20. As mentioned earlier, to deal with the DNS hijacking of operators, we can set up a reliable DNS server for domain name resolution. Nowadays, many security vendors, Internet companies and even non-profit organizations provide DNS parsing services. For example, Qihoo 360, Norton, Magic Island, Baidu, Ali, Google and other companies all provide DNS analysis services. You can also choose established free DNS services such as Open DNS. These DNS services can easily find specific IP addresses on the Internet, so I won't list them all here. Of course, this is not to say that if these DNS services are used, there will be no DNS hijacking. What if the character of these enterprises is not good? As for who is reliable, it is up to you to screen it.

21. In addition, if the operator does not provide DNS, the speed performance may not be ideal. Here to recommend a called "DNS jumper" software, you can comprehensively test the connection speed of DNS, set DNS. With the DNS jumper, this is easy

22. In addition, if the DNS hijacking of operators is too rampant, you can also complain to the Ministry of Industry and Information Technology about the hijacking of web pages. This is indeed a very effective way to the extent that some operators have directly blocked the complaint pages of the Ministry of Industry and Information Technology. So how to complain to the Ministry of Industry and Information Technology about the operators?

What if dns is hijacked? figure 5.

It is still very effective to complain to the Ministry of Industry and Information Technology about the operators.

25. First of all, in the case of web hijacking, do not complain directly to the Ministry of Industry and Information Technology. According to the process, complain to the operator first, and then complain to the Ministry of Industry and Information Technology before it will be accepted. The complaint conditions posted by the Ministry of Industry and Information Technology also include the article that "you have complained to the complainant and are not satisfied with the result of his handling or that he has not replied within 15 days", so it is necessary to go through the process first. what if the problem is solved by complaining to the operator?

However, things are often not so good, operators' answers are usually perfunctory, and customer service personnel who are not familiar with the technology do not even understand what web hijacking means. After it is invalid, you can complain to the Ministry of Industry and Information Technology about the operator!

27. Ministry of Industry and Information Technology complaint website:

28. Ministry of Industry and Information Technology complaint Tel: 010-12300

29. If there is no accident, the problem will be solved after the complaint.

Even so, if someone tampers with the UDP connection requested by DNS, it is still unpreventable. Some companies will use this principle to control employees from accessing the network casually. If you want to avoid this process, the idea is to avoid DNS using unreliable connections like UDP to query. You can use some means to set DNS to TCP connection query, or you can encrypt other servers to relay DNS requests.

31. IPV6 forces the deployment of IPSec, which can also make DNS more secure

32, of course, these methods need to be implemented, which is not in line with the use of ordinary users. Perhaps the security of IPV6 will not be further improved until DNS is fully rolled out in the future.

33. Summary

34. Generally speaking, the current DNS mechanism obviously did not take full account of security at the beginning of the planning, resulting in people with ulterior motives frequently making use of this link to affect users' normal network access. How can the current situation that DNS is frequently hijacked and poisoned be changed? Technically speaking, it is very difficult. I hope that there will be more perfect regulatory means in the future, so that users can have a better Internet experience.

At the end of this article, I hope it will be helpful to you.

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