A Content Delivery Network (CDN) is a network of interconnected servers that speeds up the process of loading web pages for applications with high traffic. CDN stands for content delivery network or content distribution network. When a user visits a website, the data stored on the website’s server travels across the Internet before reaching the user’s computer. If the user is far from the server, large files, such as videos or pictures, can take a long time to download. Instead, website content is stored on CDN servers that are geographically closer to users and can reach their computers much faster. CDN services are provided by hosting providers, cloud service providers, telecom operators, and CDN providers. As an international leader in public cloud and edge computing, content delivery, and security solutions, G-Core Labs offers CDN hosting plans to meet the needs of different web projects.
Main tasks
Content Delivery Networks (CDNs) provide many functions that improve website performance and support network infrastructure. CDNs perform the following functions
- Reduce page load time;
- Reduce the cost of bandwidth provisioning;
- Increase content availability;
- Increase website security.
Types of content
A content delivery network (CDN) can deliver two types of content: static and dynamic. Static content is website data that does not change from user to user. Header images, logos, and font styles on websites remain the same for all users because companies rarely change them. Static data does not need to be modified, processed, or generated, making it ideal for storage on CDN servers. Dynamic content, such as social media news feeds, weather forecasts, authorization status, and chat messages, is different for each website user. These data change based on location, time of authorization, or user preferences, so the site generates data for each user and interaction.
How does it work?
Most users simply leave the site if it takes more than five seconds to open, and in the case of mobile devices, the acceptable wait time is even less. It is very important to not only attract but also keep the audience because it is a matter of reputation, reviews, and advertising revenue. For online stores, where every visitor is a potential customer, the issue of audience retention and acquisition is critical. However, most of these web resources are opened fairly quickly, and we hardly notice any difference in waiting for a response from foreign sites compared to the “local,” physically deployed on the hosting site of our city.
In a classic model, the user goes to a web server, which gives them the requested content: text, images, music, video, etc. Of course, when using a CDN, there is also such a server called Origin. This is where the original data are stored. In addition to Origin, the CDN has a network of caching servers called Point of Presence (PoP) or Edge servers. They do not duplicate data from Origin, but they do cache static content, as this tends to be the “heaviest” and most difficult to deliver.
When a user makes a request to a server expecting to receive the required web page with content, the server identifies the user’s location based on the Origin data and automatically redirects the user to the server that is geographically closest (this operation takes no more than a few seconds). The Origin server typically sends only dynamic content that is generated based on the user’s specific request, and static data are sent from the nearest Edge server.
