What is a CDN?
Published: 2023-03-13 10:41:16

##Intro 
As the world has become increasingly digital, the need for speedy and reliable web content delivery is a must have in order for businesses big and small to get their content out to users. The faster the user receives their requested content, the more engaged they will be, and they will also be more likely to revisit in the future.  
It was in the late 1990s that a man by the named of Daniel Lewin noticed that internet congestion was severely limiting the speed and performance of sites depending on how far they were from the server providing the content. It's simple physics; the greater the distance the electrical signals that transmit content must travel to reach the user, the greater the load time. Another limiting factor was bandwidth. Too many users on a site at a time would commonly cause sites to crash.  Daniel Lewin set out to create a way to make content delivery faster and more reliable. His solution was the first CDN, a network of servers spread out around the world, all working together to deliver content more efficiently.

![Image description](https://techterms.com/img/xl/server_129.jpg)

## CDNs (Content Delivery Network)

The primary benefit of CDNs is their ability to increase website speed and performance. By caching website content on multiple servers around the world, CDNs reduce the distance that content must travel to reach end-users, which can significantly reduce load times. This, in turn, leads to a better user experience and can even increase website engagement and conversions. By having servers distributed across the globe, we are able to have Points of Presence (PoPs) within practically every major country, city, and town. PoPs represent a location close to the user where servers hosting copies of a site content are housed, and the edge server is the server within a particular PoP that is closest to the user. A CDN will always transmit content from the edge server to the user in order to decrease load time as much as possible for the user. CDNs also provide increased reliability and uptime by distributing traffic across multiple servers. If one server goes down or experiences a spike in traffic, requests can be automatically rerouted to another server, ensuring that the website remains online and available to users.

![Image description](https://blog.radware.com/wp-content/uploads/2017/03/cdn-security.jpg)

##Security

CDNs also play a critical role in keeping the content housed on the origin servers secure from attacks. By caching website content on multiple servers, CDNs can absorb and mitigate DDoS (Distributed Denial of Service) attacks. When an attack is launched, CDNs can detect and block malicious traffic before it reaches the origin server, thus keeping the website online and protected. Even if an attack successfully takes hardware offline, a CDN will always have another server close by that can distribute content to the user.  To detect and block malicious traffic before it reaches the origin server CDNs use algorithms to analyze incoming traffic and distinguish legitimate requests from those generated by bots or other automated tools. They can also use firewalls and other security measures to block traffic from known malicious IP addresses or to limit access to specific resources on the origin server.

By providing an additional layer of security and protection, CDNs can help keep websites online and accessible to legitimate users, even in the face of sophisticated attacks. This can be particularly important for businesses and organizations that rely heavily on their websites for their day-to-day operations, as downtime or interruptions in service can have significant financial and reputational consequences.

##Conclusion 
CDNs have revolutionized the way we deliver web content, making it faster, more reliable, and more secure. With the continued growth of digital media and the increasing demand for speedy website delivery, CDNs will continue to play a critical role in ensuring that the internet remains a fast and reliable source of information and entertainment.