What is CDN?
CDN is the abbreviation for Content Delivery Network. In short, CDN is a system that delivers content to users. In detail, CDN is a system that is much like a web server but cannot store files like a normal server.
Normal servers store the physical files of the website that we see from different websites. But CDN shows the same files on the website but from their own geographical servers.
That is, when a website uses CDN, when you visit that website, you will see a copy of that website that is cached from the main server. When you make a request to view a page in the browser, that request finds a CDN server near your location. It finds the server and shows your requested page from there.
Here, even though your internet speed is slow, the page loads quickly due to finding a server near you. If we discuss it more clearly, the matter will be easier to understand. Suppose you have a website hosted on a server in England. But all your visitors come from Asia.
So if someone wants to view your website, then after sending a browser page request, it will travel many roads to England and show the page on the browser after covering the same distance. We know that data is exchanged on the Internet through light.
Various studies have proven that no communication signal can ever travel faster than the speed of light. From this point of view, the speed of internet data is limited. Due to this limited speed, the greater the distance, the lower the speed.
But if the same website can be shown on the browser from a server near your user’s location, then the page will load much faster. From this thought, CDN technology was invented.
What is cache?
Temporary storage folder is called cache in Internet language. For example, when we visit a new website, a temporary folder is created in the browser installation folder. Where all the data of that website is downloaded. In this, when we visit that website later, the resources are brought from that folder and shown in the browser.
In Internet language, cache means downloading a full copy of a website. The advantage of caching is that it does not need to download website resources repeatedly, and the website resources load very quickly.
CDN technology system downloads the full website file from the main server in this way and stores it on each local server of the CDN. Again, when something new is added to the website, each CDN server caches it and updates the data on the caching server.
How does CDN work?
CDNs generally work in three ways. To bring content closer to the visitor, PoPs or Point of Presence method is used here. That is, many caching servers are created together, much like a data center. Each data center is placed in different countries of the world, thus reducing the entire path of file exchange.
Then each caching server caches each website using CDN. Since there are servers in different countries, when a website is visited from any location, the page is loaded from the server near that location. This not only reduces the website loading speed, but also consumes much less bandwidth.
Caching servers are usually made of SSD, HDD or RAM. However, all current servers are made of either SSD or RAM. Because SSD and RAM read and write files are much faster. Most of these servers are made of RAM. Because RAM can read and write files faster than SSD.
CDN works in these three ways. To use CDN, you need to take service from a CDN provider, such as Cloudflare. You can use CDN service in both free and paid ways. CDN can be used in all types of websites such as Blogger, Weebly, WordPress and all other areas.
However, setup in WordPress is much easier. To activate CDN on a website, you have to configure it from the domain and the main website database. You have to use CDN nameservers on the domain so that when someone wants to visit the website, it detects the CDN’s nameserver and takes it to the cache server.
CDN Security
There are many CDN services that provide SSL and other security services. For example, Cloudflare provides SSL service for free. Also, since it is a cache server, even if a DDoS attack is performed on your website, it does not work. Because your site is not operated from a dedicated server, the attack is not effective.
However, using a CDN does not mean that your website will never be hacked. Between September 2016 and February 2017, Cloudflare was the victim of an attack called “CloudBleed HTTPS traffic leak”.
In this, the data of about 7 million websites using Cloudflare CDN was leaked. The main reason behind this is that CDN uses a shared network connection. In this, if you get access to the network in any way, you can take access to all the websites on that network.
Advantages and disadvantages of CDN
Advantages
- Fast website loading speed
- Reduces bandwidth costs
- Ensures fast content delivery
- Improves website security
- Faster access to the entire world
- Local cache servers around the world can be used for a small fee
- Website is always online i.e. 24/7
- Reduces server load time
- Detailed website analytics data is available
- File minification saves storage on the server
Disadvantages
- Using a shared network connection
- Sometimes sites are blocked when using a proxy or VPN connection
- Cache servers are not fully distributed in every country in the world yet
- Website management is somewhat complicated
Question
Do you have to use CDN?
Using CDN depends on your needs. Suppose you have an affiliate website and its targeted visitors are from the US. Now there is no benefit in showing that website worldwide. In that case, if you take a server storage located in America, you will not need to use a separate CDN.
Is CDN only for WordPress?
CDN is for all types of websites. There are no special rules here. You can use CDN on any CMS or website without CMS as per your need.
Can CDN be used for free?
Yes, CDN can be used in both free and paid ways. However, the free one works pretty well. But to use advanced features, you have to use paid.
Is CDN secure?
Yes, CDN is a secure system. As technology advances, CDN system security and user experience are improving.
The world’s largest websites use CDN to cover the entire world. If you have an international website, then it would be wise to use CDN service. Also, if the website receives a lot of visitors, then CDN is also important to handle this additional visitor.