Content delivery networks, otherwise known as CDNs, are younger than the public internet, but they are older than online streaming services and high-speed wireless connections. Although a few forward-thinking companies developed rudimentary CDNs themselves, the first vendor to focus on large-scale CDNS was not founded until 1998, according to Lifewire.com. In just over two decades, the market for CDNs has grown dramatically. There are many reasons for the explosive growth of CDNs, but before discussing them, it might be helpful to review what a CDN is and how it works.
An Overview of a CDN
In basic terms, CDNs are networks of servers that are geographically located between the server that houses the content and the users who request the content. The CDN servers, which are also known as points of presence or PoPs, may be quite numerous and located in countries around the world. The PoPs cache images and other static content. When users request content, it is delivered by the PoPs that are physically closest to them.
To illustrate, suppose a company’s website is hosted on a server in India. With a CDN, a user in Australia and a user in Canada will receive identical content from two different PoPs. The same thing will happen if both users are located in the United States on opposite sides of the country.
The content on CDN servers can use either the push or pull method for caching. With the push method, copies of content are consistently copied from the origin to the PoPs. This is typically accomplished through an automated task that runs at specified intervals. With the pull method, the PoP will automatically obtain the content from the origin server if the requested content is not cached on the CDN server.
Why Are CDNs Growing in Popularity?
Originally, the primary purpose of a CDN was to reduce latency, allowing content to load faster. This is still an important function of CDNs, but as technology has advanced, the functionality of CDNs has evolved. Today’s CDNs can help reduce bandwidth requirements, which can be of critical importance for companies operating on a limited budget. In the age of cloud computing, SaaS and mobile apps, security and scalability are also important, and a CDN can help with those issues as well.
A CDN can protect against the distributed denial of service attacks that have become increasingly prevalent; CDNs simply take on the traffic. Since the content on each PoP mirrors the content on other PoPs, redundancy helps ensure that current content never simply disappears into a void. Should a CDN server fail, the load can be redistributed to other nearby PoPs that have the capacity to handle the additional traffic.
CDNs provide different benefits for users and website owners. For website owners, the benefits include those already discussed as well as the following items.
1. Google and other major search engines include the speed at which a website loads as a key factor when ranking sites. Reducing latency is especially critical for sites targeting global audiences.
2. When a site is slow to load, users tend to become impatient and leave. The bounce rate is another factor that can affect a site’s ranking in a search engine’s results page. Furthermore, a slow site can have a direct impact on the company’s revenue if the delay annoys potential customers so much that they leave without making a purchase or asking a question.
3. Modern CDNs do an excellent job of streaming videos, accelerating mobile content, mitigating bots and downloading software.
Users will likely never realize that their visits are being managed by a CDN; the entire process is seamless and transparent. However, users receive some important benefits beyond those already discussed.
1. Because the content is delivered over a shorter distance and in less time, packet loss is reduced.
2. When streaming videos, there will be less jitter, and the overall quality of the video will be enhanced.
3. The entire user experience is better, resulting in less frustration for users and encouraging them to remain on the site longer and make return visits.
When all things are considered, it is no wonder that the CDN market is growing significantly. In fact, according to an article appearing on the website, TechTarget.com, the market for CDN services is expected to quadruple between 2017 and 2022. Furthermore, the types of services included in a CDN will continue to evolve to eliminate additional issues for both users and website owners.