Web Hosting Blog
Content delivery networks (CDN) are the hidden backbone of the internet. Behind every text character, image pixel and movie frame that gets delivered to your PC and mobile browser, there is a CDN. We interact with CDNs daily; when reading articles on news sites, shopping online, watching YouTube videos or scrolling through our social media without realising it.
First off, you don’t want to get a CDN confused with your standard website hosting. These are entirely different services. A CDN isn’t a replacement for your hosting provider but rather another method to increase the speed of your site.
What is a CDN?
CDN is a network of servers across the globe designed to host and deliver copies of your site’s content. So why do you need to host your site on these servers? To increase your site speed and reduce what’s known as latency. Latency is the time and/or delay in data transmission over a network—the further the distance, the greater the latency. With a CDN, you can load your site’s content from the server closest to the person accessing the site, reducing the latency.
How does a CDN work?
As we’ve mentioned, CDNs allow you to access your data from a global network of servers each of these servers is also sometime referred to as a Point of Presence (POP). This network works by using caching, dynamic acceleration and edge logic computations.
In CDN technology, the term caching refers to storing static website content on multiple servers in the network. Caching is the process of storing multiple copies of the same data for faster access.
The process is:
- A geographically remote website visitor makes the first request for static web content from your site.
- The request reaches your web application server or origin server. The origin server then sends the response to the remote visitor, and at the same time, it sends a copy of the response to the CDN POP closest to the visitor.
- The CDN POP server then stores the copy as a cached file.
- The next time this visitor, or any other visitor in that location, makes the same request, the caching server sends the response instead of the origin server.
Caching doesn’t work well with dynamic web content. Dynamic acceleration is the use of an intermediary CDN server between the web applications and the client to reduce the server response time for dynamic web content requests. To combat this, CDN servers must reconnect with the origin server for every dynamic request.
Edge logic computations
You can program the CDN edge server to simplify communication between the client and server. For example:
- Inspect user requests and modify caching behaviour.
- Validate and handle incorrect user requests.
- Modify or optimise content before responding.
Why is it so important to increase your page speed?
No one wants to wait for a website to load research shows 1 in 4 people would abandon a site if it took over 4 seconds to load – that is 25% of your traffic; and in 2010, Google started factoring load time into their ranking algorithms.
Kissmetrics showed that a 1-second delay in page response could result in a 7% reduction in conversions, and ThinkWithGoogle’s research proved that a 1-second delay in page response could result in a 7% reduction in conversations.
How does a CDN improve your website load times?
We now know just how vital site speed is to your business; here’s how CDN services can help to reduce load times in the following ways:
- It reduces the distance between users and website resources. Instead of connecting to the website’s origin server, which may live far away from them, a CDN lets users connect to a closer data centre -less travel time means faster service.
- Hardware and software optimisations such as efficient load balancing and solid-state hard drives can help data reach the user faster.
- CDNs can also reduce the amount of data transferred by using tactics to reduce file sizes, such as minification and file compression. Smaller file sizes mean quicker load times.
What are some other benefits to having a CDN?
Redundancy and scalability during high traffic times: Because they use multiple servers, CDNs handle hardware failures better. If one server goes down, another server picks up the slack. Additionally, when traffic spikes, a single origin server may not be able to handle the load. Since CDNs are located all over the globe, they spread traffic over more servers during high-traffic times and can handle higher traffic volumes.
Lower bandwidth costs: Bandwidth costs are what you pay to move your data around telecommunications networks. The distance your data travels, and the speed it needs to get there determines the amount you pay in bandwidth costs. A CDN’s caching reduces the need for content to travel as far, thus reducing bandwidth costs.
At CWCS, we offer Comodo cWatch Web; a Managed Security Service supported directly by Comodo. Designed for websites and applications and includes a Web Application Firewall (WAF) and Advanced DDoS Protection, provisioned over a Secure Content Delivery Network (CDN).