Starting from now we are going to publish series of survey articles dedicated to performance metrics for content delivery networks in different regions or strategically important countries worldwide. The peculiarity of these articles is that the data used for the presentation is collected with PerfOps Real User Monitoring. In a couple of words: regular users, who trigger PerfOps RUM-script on our partners' sites, provide us with huge number of daily CDN tests (recently we went over 1 billion tests in 24 hours period). This massive amount of tests done every single day, provide us a with a very realistic image of the best CDN providers in China, USA, Russia and all the other countries.
As a disclaimer, we have to emphasize that this research was done only using CDNs monitored by PerfOps analytics system. We do not yet measure some big China local content delivery networks like Aliyun, Baishan, Baidu, Kingsoft, but we hope it's just a matter of time until we start (and this will be a call for another article on China CDN performance). So, if you are reading this, you are a CDN Provider, and you want the PerfOps RUM system to monitor your resources - feel free to reach out.
As you can see from the title, we have decided to start our series with the article, dedicated to Content Delivery Networks performance in China, the one of the largest countries in the world, where Internet and online services show the fastest growing in 2020 and the number of internet users already exceeds 900 million!
What's so special about CDNs in China?
- All domains that serve content from servers located in mainland China must have an ICP license. That ICP license, in fact, is a permit issued by the Ministry of Industry and Information Technology to allow local-based websites to operate in China. The problem is, only Chinese companies can obtain it, no foreign companies are allowed.
- The whole access to foreign information sources is limited, or filtered by The Great Firewall of China - it blocks access to some foreign websites and slows down cross-border internet traffic (these 2 challenges are a good reason to test a multiCDN solution with a global and a Chinese CDN in your multi CDN stack).
Despite on such limitations, China has near 10 powerful providers with a lot of Points of Presence. If we count the number of POPs, we see:
- Kingsoft Cloud with 600 POPs;
- Quantil with 550 POPs;
- ChinaCache with 500 POPs;
- BaishanCloud with 500+ POPs.
CDN Performances in China according to the PerfOps Analytics.
Let's analyze the data provided by CDN providers that are being monitored with PerfOps RUM testing. We have made a short analysis and selected 'top 10' with the best performance in China:
The analysis above was done by 'mean' (average) function in our analytics dashboard. Now we will show you the performance of these best performing CDNs in China using different functions, so we can present you a comprehensive picture of which content delivery network is the best for you.
Let's get our statistics for the last 7 days with 1-hour step. And start with the Median function, select it, apply filters and get a lot of information:
We get all graphs, but all we need is to find the providers with the lowest latency, the lower latency means the better performance. Our PerfOps panel is pretty user friendly, graphs can be turned on/off, and a nice popup shows latencies at the particular point of time. And we can see, the best results are shown by CDNetworks, it is followed by Cloudflare. Google Cloud CDN, Azure CDN and ChinaCache are one step behind with nearly similar values.
Now, let's check our Mean (Average) function:
CDNetworks wins the prize again! Cloudflare CDN get the 2nd and ChinaCache gets the 3rd place.
The Panel can also provide Percentiles statistics. Let's check the 'Percentile 75' function first:
The 'leaders' are the same as we had before. Let's do it now for the 'Percentile 90':
The same leaders, and they remain the same for the 'Percentile 95':
It is really incredibly interesting to see the 2 digits performance for CDNetworks even on the highest percentiles! Cloudflare is also amazing, being under 200ms even on 95 percentile. On the other hand, we see ChinaCache has very good performance in mean, median and even in 75 percentile, but are far from CDNetworks and Cloudflare when we move the percentile to 90 and 95. This tells us that in the good scenario all three of them are really fantastic solutions (with Google and Azure as well), but for the more challenging network/local conditions situations, Cloudflare and CDNetworks differentiate from the competition.
Ok, we're done with our functions, let's check Uptime statistics, because no matter how good latency is - a poor uptime can spoil the whole performance. And the best rule is: "Reduce latency and avoid downtime!"
And the picture is different, the best service providers with the best Uptime here are Cloudflare, Azure CDN and ChinaCache:
So, we can tell, CDNetworks is the leader everywhere related to Performance, but has some Uptime issues. Whereas Cloudflare, Azure CDN and ChinaCache show better Uptime. It's also notable that both Cloudflare and ChinaCache are in the top three in 'Performance' and 'Uptime' tests.
As you can see, there are good and not that good choices, but... there is no 'one CDN to deliver them all'. The best approach is to use a combination of them and have the lowest latency all the time, while having 100% uptime as you would always reroute your user to the available CDN, as well as the best performing one (you can use FlexBalancer to achieve this).
You might also notice the Cache Ratio in our analytics dashboard - it is the ratio of how many 'edge vs origin' hits were made for each provider. Super important metric as well, but we let you discover that one on your own in our analytics dashboard ;)
We believe that in near future we will be able to monitor more providers as well (including mainland China CDN providers), so this article is not the last related to China performance. And finally, if you got any questions regarding the article, CDN or anything else around the network infrastructure, just shoot us an email to firstname.lastname@example.org.
We are always glad to talk with you!