On a daily basis, we use the Internet and surf the whole world from sitting at our desks. Have you ever wondered how the content from one part of the world is delivered to us in just a snap of a second? If Yes, let me tell you about CDN and how it makes our life easy.
What exactly is a CDN?
Content Delivery Network (CDN) refers to the backbone of the Internet to deliver content to the users. Whether you know it or not, we use CDN every day.
In simple terms, it is a geographically distributed group of servers around different areas to provide fast delivery of Internet content to the users.
A well-configured CDN helps users to get Internet assets like files, sheets, images, videos in a quick time. Similarly, it also helps users against common malicious attacks like Distributed Denial of Service (DDOS) attacks.
How Does It Work?
If you are not familiar with CDN from before, you may still have some doubts about understanding CDN even after reading the above paragraphs. Therefore, we have included an example to understand CDN easily and how it works.
Imagine you are in Dallas, and you want to view your favorite store’s website content that is in Tokyo, which is hosted on a server in Japan. So if the content had to travel this distance, it would take higher delivery time, right?
So to avoid these kinds of problems, CDN is set up around different areas of the globe, which contain cached versions of the website. These points are called Points of Presence (Pops).
Now, when you want to access your favorite store’s website’s content in Tokyo, you will be connected to the point near you, which contains the cached version of the website, hence the website content is delivered to you in a short time.
Main Purpose of CDN
After reading the example, you may have an idea of what CDN’s primary purpose is. Yes, it is to provide Internet content faster to users, making them happy. It’s annoying when you experience some delay when some content takes a lot of time to deliver to you, right? Even a few seconds like forever.
So to avoid problems, most CDNs solve these problems by reducing the physical distance the content needs to travel. Therefore, the more the distributed servers around the area, the quicker the files are delivered.
The files you send once in the CDN are cached and stored there. The files include all the files, sheets, media files that may be of 4k and HD-quality too. And, whenever someone on the Internet requests these files, they are sent from CDN.
Even if the files may be outdated, the CDN stores newly fetched content to serve future requests.
How is a CDN built?
So now you know what CDN is, how it works, and all. But how is a CDN built? The building blocks that are used in creating CDN are:
1. Points of Presence (Pops)
As mentioned earlier, Pops are strategically located data centers around different locations responsible for connecting the users inside its radius.
The main goal of Pops is to reduce the round trip of the user’s request to the original server and bring the content closest to the user, resulting in faster delivery of the content.
2. Caching Servers
Each pop contains numerous numbers of caching servers in them. The caching servers are responsible for storing and delivering those held cached files to the requesters.
The primary purpose of the caching servers is to reduce bandwidth consumption and reduce website content load times.
3. RAM & SSD/HDD
Storing those large numbers of cached files needs ample space. Therefore, CDN is built-in with the hard-disks (HDD & SSD) or RAM (Random-Access Memory). Comparing the three, RAM is the fastest and is used by most CDN to store the most frequently accessed data files.
Benefits of CDN
So what are some of the benefits you can get with CDN? Is it that important?
The benefits of CDN can be categorized into different components depending on the size and needs of your business.
Some of the components are as follows:
1. Improving Website Content Delivery Time
By using nearby CDN, the website contents are delivered faster, which means an excellent experience to the users. Users who experience this tend to stay on the website longer than the slow-loading web pages.
According to the Unbounce Report, 70% of users admit that if the website content is delivered to them faster then it impacts them to buy from those online stores or retailers. So you can clearly see that your business is affected.
2. Reduce Bandwidth Costs
Using CDN is not free; it costs money. Whenever an origin server gets requests from website owners, bandwidth is consumed. According to the data consumed by the origin server, this bandwidth costs to deliver content to the owners.
First of all, the distance is reduced by using the nearby CDN. Then, by caching process and other optimizations, the amount of data used by the origin server is minimal, reducing the costs for website owners.
3. Content Availability
There is a high chance of website traffic or hardware failure when a content must deliver from a long distance, and various things can harm the flow of the content from a source to its destination.
So looking at these problems, well-distributed CDNs are set up. These CDNs help to handle website traffic and other hardware failures. Even if one or two CDNs are down or go offline for some reason, other CDNs can pick up their website traffic for a specific time to let the system uninterrupted.
4. Improve Website Security
As I said earlier, CDNs help to deliver content to the users faster but also helps protect your website data from various things.
Let’s have a more in-depth discussion about it, shall we?
By Providing TLS/SSL Certificates
Whenever data must be sent from one place to another, it becomes vulnerable and can be hacked on the way by malicious personnel. So a particular protocol must be used, which helps encrypt these data, and only a designated person can encode and read the information.
Transport Layer Security (TLS) and Secure Sockets Layer (SSL) are such protocols that are used for such encryption of data. These certificates ensure that specific protocols are used during the transfer of data between the website and the user.
So CDNs provide these certificates to the websites, ensuring the highest level of authentication, encryption, and integrity.
To check if the website is well secured or not, check if it starts with HTTP:// or HTTPS://. The HTTPS:// means that it is TLS and SSL certified, and HTTP:// means it is not secured.
Block Crawlers and Bots
As aforementioned, bandwidth consumption costs money, and you cannot let others use it.
So CDNs help websites block threats and limit the crawlers and bots from using the bandwidth and other vital resources.
As a result, it avoids hack and spam attacks and keeps the bandwidth cost low every time.
Mitigating DDoS Attacks
The CDN functions as a virtual high-security fence against attacks on your website and web application since it is put at the network’s edge. Due to its dispersed architecture and on-edge location, a CDN is perfect for stopping DDoS floods.
Because these floods must be dealt with outside of your primary network architecture, the CDN will distribute them to multiple points of presence (PoPs) based on their origin, avoiding server saturation.