Can Chinese people use this web in China

How the china great firewall affects the performance of websites outside of china

The Great Firewall of China, or as it is officially called the Golden Shield Project, is an internet censorship project that prevents people from accessing certain foreign websites. It is the most advanced and extensive internet censorship program in the world. This project implements several techniques and tactics to censor China's internet and controls the internet gateways to analyze, filter and manipulate internet traffic between inside and outside of China.

The reasons for this internet censorship are many, but most of them are in favor of favoring the Communist Party's internet policies for political gain. In this way, China is also able to force people to use Chinese alternatives for websites. For example WeChat and Weibo, which further allows the government to control the content that is published on such platforms.

Well, in order to have a deeper understanding, the censorship by the Great Firewall of China not only blocks individual foreign websites and service providers, but also extensively scans URLs and websites for blacklisted keywords, among other things with nice technical tricks to keep Internet traffic in Control China.

The how and what of the Great Firewall of China

The Great Firewall of China is something that cannot be deciphered directly with transparent guidelines. It's a complex architecture with multiple layers of controlled tricks to block access to websites. It's designed so that you won't even notice if the website has been blocked. For example, if you land on a blocked website, you won't see any warnings or information about it. Instead you will be loading forever and other messages like timeout, connection failure, network problem, etc. This makes it very difficult to know what happened and you can only guess what the real problem is. Let's take a look at various methods built into the Great Firewall of China.


DNS poisoning / spoofing. Each website request first goes to the DNS server to get the website's IP address and access the address it replied to. If the DNS answer is wrong, you will not be able to access the website. If the DNS caches are manipulated to contain incorrect IP addresses, it is known as DNS poisoning. China is doing just that to block well-known websites.

Blocking IP access. This is a well known and widely used technique that is also used by The Great Firewall of China to prevent access to multiple IP addresses. Even if you try to access the website using the correct IP address of a website, you will not be able to access it if that IP is blocked by this technique.

URLs analysis and filtering. China's firewall can block the entire website or selective websites based on the requested URL scan for blocked keywords. As a popular example, before China completely blocked Wikipedia in all languages, Wikipedia was accessible from China, but the Wikipedia article on Internet censorship in China was inaccessible due to the use of the keyword "Internet censorship".

Deep packet inspection. Deep Packet Inspection (DPI) techniques are also used by China's Great Firewall to extensively inspect incoming and outgoing unencrypted network traffic for packets, filtering and blocking data packets that contain sensitive information that is being censored by China.

Reset connections. The Great Firewall of China also uses the trick to reset connections between two communicating devices / servers as long as the transmitted data is qualified as sensitive data. This essentially means that after blocking the data packets, the firewall can also reset the client-server connection for a certain period of time.

Block VPNs. What to do when a website is blocked You are trying to access it through an encrypted VPN. Well, the Great Firewall of China is constantly learning the evolving attributes of VPN traffic in order to end known VPNs as well as new VPNs.

Legal corporate censorship. As you may have guessed, in order to orchestrate the level of censorship carried out by the Great Firewall of China, Chinese companies are also legally bound not to divulge sensitive information that is being censored. And if they do so, knowingly or unknowingly, they will face a hefty fine and penalty.


What does this mean for your websites and applications?

As we said earlier, the way China polices internet traffic isn't completely transparent, but you now have a pretty good idea of ​​what the Great Firewall of China is capable of. What does this mean for your company? Let's take a look at some issues your website or application may face when accessed from China.

  • If you have any sensitive information anywhere on your website or application that you do not know, you will be blocked, at least partially, if not completely.
  • If you use third party services that are blocked in China, even if they contain open source libraries from blocked vendors, your websites or applications will not work properly or even be inaccessible from China.
  • If you run ads from Google Adsense or other blocked companies along with banned ads in China, they won't appear on your page and your websites or applications may also be restricted.
  • As the traffic to your website or application is subject to intensive inspections, you will face constant problems with the speed and performance of the website.
  • China has a huge population so your website or application will face a lot of stress during peak hours, such as mornings and afternoons, which will cause performance problems.


Again, it is difficult to predict all the types of problems your website or application will encounter in China because the censorship is not transparent. So let's see how best to approach and strategize to make sure your websites and applications are working properly in China.

How to Bypass China's Great Firewall: Approaches and Solutions

Internet and information are free birds by origin. You can best try your level to censor the internet and withhold the information, but you can't block everything. That is the case with the Great Firewall of China. As censorship evolves, so too do the approaches and tools to counter it at the same time. Here's how to address the issues caused by censorship using available tools and techniques.


  • Monitor your website speed from China. With a large population and censorship, websites in China are behaving differently with a monitoring tool that gives you the ability to monitor your website speed out of the china so you can identify and optimize it.
  • Monitor third party services from China. Since your website could be perfectly fine but the problems with third party services can barrist your website, you need to monitor it thoroughly from within China with a good web service monitoring tool.
  • Pairing with a local CDN. For example, to increase website speed and reliable content distribution, you can opt for a local Chinese CDN such as Alibaba Cloud or Baidu Cloud.


Conclusion: website performance monitoring from China

In summary, once you enter the Chinese market and have identified a large user base there, it is important that you continuously monitor your website performance from within China and identify ongoing performance issues. Monitoring from outside the Great Firewall of China from external locations is not enough. Choose a surveillance solution with the ability to test your website from multiple geolocations, including China. Dotcom-Monitor offers a number of free online performance tools to check the performance of your websites, applications, servers, and more from China and other global locations.

Or try out the complete Dotcom-Monitor platform for 30 days free of charge.