If you're browsing websites or using an application connected to the internet, chances are high that you're interacting with a CDN. A CDN, or a Content Delivery Network, helps people obtain online content faster and reduce latency.
What's latency? That's the annoying delay between clicking a link and seeing the webpage loaded, or a several-second buffering of a YouTube video after you've clicked play. Latency is the delay between the moment you click to access online content and the moment you see it.
One major cause of latency is distance. The farther away you physically are from the responding server when you make a request on a website, the longer it takes for the content to appear. CDNs speed up the delivery of content to end users by closing the distance.
What is a CDN and how does it work?
Made possible by the cloud, A CDN is essentially a network of servers spread across a wide geographical range to reach users all across the globe, consisting of an origin server and an edge server.
An edge server refers to each individual server in a CDN, as they are located in closer proximity to users in what is called the "network edge". Edge servers store a cached version of online content from different platforms, such as a website or mobile application, from the origin server.
The origin server hosts the entirety of the original platform and its content, reflecting any updates made to the website once they are published.
The shortened distance between the edge server to users allows the website to load its content faster, reducing latency and improving the overall user experience.
Hosting a website on a CDN vastly improves its performance as compared to hosting it on a single origin server. Here's how:
A user in Japan accessing a website that is hosted on a single origin server in the United States would experience a longer load time, as the request has to travel a farther distance to reach the user.
With a CDN, the origin server would be linked to several edge servers in different geographical sites, called points of presence (PoPs). Each PoP responds to requests that are made within its proximity. When a user makes a request, CDN service providers or management software will calculate which PoP is closest to the user and deliver a cached version of the website from there. In this instance, the user in Japan will be able to access website content faster from a PoP in India, as compared to accessing the origin server in the United States.
With a CDN, you can access information and use the internet faster - watch video clips, download apps, read news online, or make purchases at at a higher speed.
CDNs vs Traditional web hosting
It's important to make a distinction between CDNs and traditional web hosting servers. They aren't the same, and CDNs can't replace web hosting either.
Essentially, a web host is the origin server responsible for hosting the entirety of a website with all its different content forms. The load time of the website increases if the website is accessed from a server geographically located farther away from the web host.
Meanwhile, a CDN doesn't host an entire website, but provides a temporary, cached version of it with static content on the edge servers. This allows website content to load much faster for users, having been delivered from the PoP closest to the user over the shortest possible distance.
The table below compares the key differences between a CDN and a web host.
Benefits of using a CDN
Although CDNs are known for their ability to improve web loading times, they have several other advantages. They can help you and your business in many ways.
1. CDNs can improve web performance
Faster web loading times As CDNs shorten the distance between the user and the stored content, the user experiences faster website loading times. CDNs also use other techniques to speed up websites, for example, minification, file compression, and SSL certificates.
Content optimization Websites now offer more varied media formats and services which require high levels of performance, such as video streaming, e-commerce and cloud applications. To deliver fast, high-quality multimedia web experiences and meet the needs of their users and customers, using several CDN providers is essential, especially for an international customer base that uses multiple device types.
2. CDNs can increase content availability and redundancy
Websites can be overwhelmed and brought down by vast amounts of traffic, through increases in popularity or malicious attacks. This causes hardware failures, preventing users from accessing a site or service, especially if they are hosted on a single origin server. CDNs are designed to ease the burden of the origin server. With their distributed architecture and large server platforms, CDNs can handle high amounts of traffic by absorbing hundreds of Tbps and reduce the chance of data failing to load. Here's how:
Load balancing scales and distributes traffic equally across various servers to prevent websites from crashing due to a high volume of requests. The website can hence continue providing uninterrupted service to users.
Should one or more of the CDN edge servers become inoperational due to any malfunctions, intelligent failover redirects traffic to other operational servers. Hence, the content on a website always remains available.
Effective marketing campaigns, limited-time discounts, viral videos, or other similar events can create rapid spikes in content demand. In response, CDNs equip websites to successfully handle high traffic spikes and consistently deliver their content to users without website performance being negatively affected.
3. CDNs can increase user engagement and satisfaction
Poor site performance, such as slow load times and media playback issues, are responsible for users abandoning or avoiding websites. These performance issues can be prevented or minimized with a CDN, improving user experience with faster application responsiveness, quicker web loading times and reduced video buffering.
Additionally, CDNs may monitor website traffic to gather data about visitors to a site, such as their metrics and behavior. By tracking real-time analytics, website and application creators can optimize content and marketing efforts to their userbase by tailoring it to their specific needs.
Therefore, improved user experience and optimized content result in higher user satisfaction. Users are then more likely to stick around on a site and engage with its content and services, increasing user retention, lowering abandonment rates, driving higher conversion rates and strengthening consumer loyalty.
4. CDNs can reduce bandwidth consumption and infrastructure costs
Bandwidth is consumed each time an origin server responds to a request. Using caching and other techniques, CDNs can reduce the amount of data the origin server needs to provide. The bandwidth consumption and related expenses can thus be considerably lowered, which is one of the main costs for websites.
Organizations can also outsource infrastructure support by using a CDN. Without needing to construct and maintain geographically distributed server networks, time, money and labor is saved, hence reducing infrastructure costs.
5. CDNs can enhance site security
With vast amounts of traffic travelling to and from CDNs, they are a prime target of cyber attacks. Common CDN security concerns include information breaches and distributed denial-of-service (DDoS) attacks.
Information Breaches: As CDNs cache information and content, cyber criminals can exploit CDN edge servers to gain illegal access to sensitive information, such as passwords and e-mail addresses. They can then log into private accounts or hold the data at ransom.
DDoS attacks attempt to shut down CDN servers by sending in more requests than they can handle, overloading them and making the website unavailable.
Fortunately, CDNs have information security strategies integrated into them to prevent such attacks and improve the security of a website. To protect against DDoS attacks, CDNs use WAFs, analytics and automation to monitor and detect when these attacks happen, blocking them by limiting request rates. CDNs also use TSL and SSL certificates to create secure communication between the origin server and the CDN, and between the ISP and the CDN, preventing information breaches.
Who uses CDNs?
Everyone (End users)
Anyone on the internet is using a CDN. All sorts of content and services go through CDNs, including websites, mobile applications, file downloads, search engines, social media, e-commerce sites, media streaming services, video platforms, and online gaming.
Although we might be unaware of it, we benefit from CDNs on a daily basis. Websites load faster and transactions are completed quicker, providing a consistent and high-speed online experience.
Content owners
On the flip side, if you run any sort of website or application, such as an e-commerce site or a SaaS service, CDNs can help you, particularly if you have a large user base that stretches across a wide geographical range. Apart from enhancing site security and lowering bandwidth costs, CDNs help provide an improved user experience for a variety of services.
Some CDN use cases include:
Media streaming platforms and communications companies providing video calls, live video streaming and video content, ensuring high-definition sound and image quality, fast transmission and minimal to zero buffering or jittering for their services.
Web and mobile e-commerce storefronts rapidly loading product images and quickly processing purchase orders with fast payment method approvals, during busy times of the year when traffic spikes.
Banks and financial institutions securely transferring sensitive customer data.
Organizations with strict security needs or specific geographic requirements using a private CDN with its own dedicated edge servers with high availability and no latency.
Mobile applications reducing load times and increasing response times to improve the mobile user experience.
Online multiplayer games running smoothly at advanced graphical settings without lag or jittering, and video game distribution platforms downloading game files and patches at rapid speed.
Network service providers
CDNs ease the burden on the origin servers of network operators by offloading traffic. When traffic spikes, the origin server is hence less likely to crash and become inoperative. By reducing traffic, network operators can thus reduce the chances of losing subscribers or customers, who may leave and not come back after encountering a site or application that's currently down, or worse, cancel their subscriptions due to the deteriorating quality of content and services.
Additionally, deploying a CDN can accelerate the development of other value-added services and enable network operators to sell CDN services to other companies and third-party content owners.
Hi Cloud CDN solutions
As a professional cloud solution provider, Hi Cloud partners with major cloud providers - Azure, AWS, Google, Alibaba, Tencent, and CloudFlare -to bring you the best CDN services. Learn more about our CDN services or contact our cloud experts and book a free consultation now.
