Choosing the right CDN
The concept of CDN (Content Delivery Network) should be as familiar to broadcast professionals as a transponder from a satellite or DTT are. After all, they all serve a similar purpose: transporting content from the point of creation to end users. We are going to try to explain this concept a little more in detail and see what considerations must be taken into account when choosing our CDN provider because certainly not all of them are the same.
By Yeray Alfageme
A CDN (Content Delivery Network) is a set of servers that are located in different parts of the world and which have local copies of the hundreds or thousands of content items that the main website has, such as, for example, images, videos, music, documents, web files, etc.
The idea is that the largest and most important services can have their website contents mirrored on different servers spread around the world which are, in general, are geographically remote. With this, all end users would have a server physically close to them and this implies that they are able to access content in a more efficient way.
These content distribution servers achieve a better balance of the web traffic load to which the servers are subject. This improves efficiency and is noticeable both on the servers that host the content and on the links that interconnect the different sections of the network. With these CDNs, potential bottlenecks when people access a website are eliminated and latency and access speed are reduced.
This architecture is more important the greater the amount of information to send to end users. A CDN does not have as much impact on the website as a written newspaper or a static page that does not change much, but it is very important on OTT or content creation platforms; in fact, it is a key component.
Large platforms invest a lot in this regard. Many of them have their own private CDN structures in order to guarantee a quality of service above that of their competitors, but for common individuals, this is not the case. The usual procedure is to make use of the different CDN solutions offered by providers such as AWS, Akamai, Google and other large Internet players. Its infrastructures are practically impossible to match.
But what should we take into account when choosing a CDN? Well, perhaps the main component is that the business model fits in with ours; but let me explain. If we have a CDN provider that charges for content availability by the hour and our advertisers pay us for the number of times the content is played -which is typical- it is obvious that there is no fit. Our provider will be interested in making the content available for as long as possible, thus avoiding the need of archiving and deleting it from our platform, whereas we will be interested in getting such content played as much as possible. In the long term, this will lead to frictions and deviations, and not only financially, but also in terms of features of the service that will cause us great headaches and problems.
Another issue to take into account, which is connected to the previous one but not exactly the same, is the billing method. If our provider charges us for traffic -i.e. gigabits or terabits delivered to our end users per month- instead of for the number of hours of viewing, or vice versa, our profit-and-cost model must be adapted accordingly, or rather the other way around. And it is not only a financial issue, but also a technical one. For the design of the architecture and content structure of our platform we must take into account how this content is going to reach our end users; it is a critical issue.
Last but not least, we must ensure that -technically- the CDN meets our requirements. I have left this matter for last as these technologies are increasingly becoming widespread and all providers are similar and capable of delivering any type of content without problems. However, we must take into account two details: the geographical location of the CDN servers and the content protection features that the provider may offer us.
In especially challenging locations like China or Africa, two CDN providers will offer very different performance levels and features, and this will be key in our choice of service.
The top 5, or something like that
The providers that we are going to mention below do not imply any official ranking but we are basing this on the knowledge we have of them and their involvement in our specific broadcast market. All of them are known to most professionals. This does not mean that they are better or worse than the rest or that the first is better than the last. It is simply a short reference list to compare them and have real examples of what we have outlined previously.
Akamai is one of the largest providers and one with more options available, although it does not show prices on the website and we must register and then contact a consultant. There is no need for a payment method to try it and it has a free option for 30 at no cost, which we can test if we register on the website by providing some basic information such as name, email address and company. If we like it, we can get in touch to choose a plan.
It is a network that has more than 1,400 options in different countries. In total, in more than 130 of them and over 300 Tbps of capacity. It has services and tools for account management, performance metrics, online video and cloud computing.
Akamai has three different solutions that we can consult from its website: Aure Edge eXchange, Aura Control System, and Akamai Federation. In content distribution, the possibility of offering high-quality videos, large file downloads, specific distribution or the possibility of analyzing the performance or participation of users using the CDN stands out.
Another of the most popular CDNs in the world is Fastly. As with other providers on this list, several payment plans are available according to the relevant needs, including a free-trial period. We can choose between the Essential, Professional or Enterprise plans. All of them are designed for companies, but we will choose one or the other depending on company size or the audience we want to reach, for example.
Fastly has an infinite number of configuration options and another of its strengths is the possibility of choosing between different types of cache when generating videos. It is also the CDN used by firms such as Twitch, HBO or FuboTV. The service allows them to work smoothly and without cuts or interruptions regardless of where we access them. It is also behind others such as Hulu or international media such as The Guardian, CNN, The New York Times…
AWS (Amazon Web Services) is Amazon’s division in charge of cloud computing services. Among the services and tools offered we find Amazon CloudFront. It is the content delivery network or CDN. As they themselves explain on their website, it is “a fast content delivery network (CDN) service that distributes data, videos, applications and APIs to clients around the world in a secure way, with low latency, high transfer speeds, and within an intuitive environment for developers”.
It has all kinds of benefits, advantages and, also, multiple uses. It is intended for on demand video or live video streaming. In addition, it also allows improving security or “speed up delivery” of the website by reducing the load on servers or improving latency times.
There are many companies around the world that use CloudFront as a CDN. From Amazon Prime Video itself to other successful companies such as Slack, King or Rovio, as well as brands such as Canon, the Condé Nast medium or Nextdoor company.
Prices vary depending on the country and also on data transfer rates, but we can check them in the website. In addition, there is a free-use layer from AWS that allows to start using Amazon CloudFront at no cost, although with data transfer limits of up to 50 Gb or a maximum of two million HTTP or HTTPS requests. We can also contact the company to get customized prices.
Cloudfare has a network of servers in more than a hundred different countries, and this makes it one of the most recommended options that we can consider. There are servers in more than a hundred cities around the world and we can get a detailed view in their website. In Spain, Cloudfare has offices in Madrid and Barcelona.
Cloudfare describes itself as a massive global data center network. It is a fully customizable CDN that allows you to choose what you need and what not, as well as choosing page rules or having control over how the content is stored. Its advantages include the greatest bandwidth savings or the possibility of a detailed control on the cache memories in order to know what resources are stored or to have a control panel that offers details about performance, as well as filters allowing to monitor everything happening on the web.
It supports video services and also the HTTP/3 protocol. As for video, it is compatible with file types such as MPEG-DASH, HLS and CMAF. It also promises support for BYOIP addresses and has other features like support for China, for example. It also has extra or additional functions such as the ability to block bots, block spam or a control for blocking cyberattacks. These features will improve the security of the website.
Cloudfare rates vary based on what we want to have. There are free packages at no monthly cost, but also other solutions featuring more options. They are the Pro, Business or Enterprise packages. Prices are $ 20 or $ 200 a month for the first two, while the Enterprise plan does not have a fixed rate and an estimate must be requested.
Transparent Edge CDN
This is another of the best options when choosing a CDN. Among the clients that we find in this CDN, there are many of the essential Spanish websites, such as RTVE, the Vocento group, Codere, the Spanish Association Against Cancer or the Funidelia or Agatha Ruiz de la Prada stores.
In the Transparent Edge Service locations we see that this network has servers all over the world. In Spain there are offices in Madrid and Barcelona, but the network has offices also in Paris, Geneva, Zurich, Milan, London, New York, Washington DC, Chicago, etc.
Services are divided into five main categories: content distribution, security, computing, access and platform management. Within each category or section we can see the benefits and options that they enable.
It is a service that allows you to access a dashboard to view all the details for the services. In this panel or desktop we can see performance metrics, geographic location filters, the services that we have hired or that available for interaction in real time, in addition to integrating other tools supported by Transparent Edge.
Of course, we are not going to decide here which the best CDN is because it would not be fair and we are not capable of doing so without having an in-depth knowledge of everyone’s business model. As previously stated, the decision must be guided by the idiosyncrasies of our business and taking into account both costs and billing model.
Technically almost all providers offer the same features. Geographical location, one of the keys to the service, must weigh in our decision, as well as the specifics of our requirements, such as the necessary security or any other detail that we consider relevant.
As it seemed, there are many providers operating on the market and our CDN must be as important a system, or more, as our terrestrial distribution network; always taking into account the characteristics of the growth that digital services are having when compared to conventional ones.