What is a CDN: A Guide for Beginners
Each one of us interacts with content delivery networks (CDNs) on a regular basis while reading news on a portal, shopping online and browsing our social feeds whether we know it or not. For those of you who are wondering what a content delivery network (CDN) is, it is simply a network of servers located in data centers across the globe.
Before you dwell deeper into what a CDN is, let us first understand the issue they are designed to solve. CDNs solve the problem of latency i.e. the delay that occurs from the moment you request a webpage to the moment its content appears on your screen.
Latency arises on account of many factors, the most important being the physical distance between you and the server on which the website is hosted. A CDN reduces that physical distance, delivering enhanced speed and performance.
How does a CDN work?
A CDN stores a cached version of the content of your website in multiple locations (called as points of presence or PoPs). This content may be in the form of HTML pages, images, videos or JavaScript files. Every PoP consists of a number of caching servers that deliver content to users in its proximity.
When users load a webpage, they receive this content from the PoP that is geographically closest to them. A CDN is different from the conventional method of storing data on just one central server.
A CDN can enhance the performance of your website to a significant degree. It can improve your website’s speed, performance and ensure all users access your content with the same ease no matter what their location is.
No wonder, over half of the traffic on the internet is being served by CDNs. And the numbers are rising every year.
If you are a growing website that has started receiving high traffic, it’s time you should start considering a CDN for your business.
Let us discuss the advantages and disadvantages of using a CDN.
Advantages of using a CDN
1) Faster Content Delivery
Because CDNs involve servers placed closest to the user, they reduce network latency, allowing the content to be delivered much faster. For instance, if your website is based in India and you get a lot of traffic from the USA, your cloud CDN hosting provider may have a server in the USA that you can use for your website.
2) Global Access
CDNs make your content globally accessible. They prevent the problem of content source and destination through multiple points of presence (PoPs). This allows you to carry out global business transactions and prevents the incidence of slow or unsuccessful transactions. All this helps you go global.
3) Less Network Congestion
Your website performs better when congestion rates are lower. Network congestion happens when a large number of users try to access a site at one time. Cloud CDNs redirect users to replicated content, leading to lower congestion, higher performance and overall better user experience.
4) Enhanced Reliability and Trustworthiness
The content delivered through CDNs has high quality in comparison to the one delivered through other sources. CDNs are designed in such a manner that they distribute content at a faster rate. This allows for higher customer satisfaction and trustworthiness.
5) Lower Overheads
CDNs eradicate the need to pay for costly foreign services and multiple service providers. You can make your content globally available with the help of a single CDN hosting provider. You can allocate traffic to a higher number of nodes in order to make the content available widely.
Disadvantages of using a CDN
1) Pricing
Pricing is one of the major downsides of using a CDN. Cloud CDN hosting is expensive and may involve many hidden costs. These may involve costs per data transfer.
Setting up a CDN network requires a hosting company to receive help from third-parties to install the network. This results in high costs for the company which is passed on to the customer. CDN networks are, therefore, suitable only for businesses who can afford such high costs.
2) Location
If most of your users are in a location where there your CDN provider does not have any servers, the content on your website may need to travel further without any CDN. It is, therefore, essential, to find out the location of servers of your cloud CDN provider before finalizing a service. Of course, you won’t pay for servers that are located far from your users. This will increase network latency and reduce the performance of your website.
3) Restrictions
Many popular CDNs have been blocked by certain countries and organizations. So, if your audience belongs to any of these countries/organizations, they will not be able to access your content and you will end up losing traffic.
4) Support
If a third-party service provider is running the CDN, the question of availability of support arises. You don’t know how long it is going to take for the technician to fix an issue and prevent it from happening again. This can hamper the experience of your visitors.
5) Loss of Control
As already discussed, CDN service providers usually seek the help of third-parties to install the network. If you are using a cloud CDN, the third-parties involved will receive information about your website and its files. This is something you need to take into account before deciding to use a CDN.
Wrapping Up
CDNs improve the speed and performance of your website significantly by catering to users in multiple locations. If you run a local website where most of your users are in the same location as your hosting server, using a CDN makes little sense. In this case, a CDN can actually worsen the performance of your website by bringing in a redundant connection point between the user and the already close server. If, however, you have a high-traffic website that serves users in different geographies, a CDN can be a good bet for you.
