Top CDN services can be hard to identify for potential content delivery network customers. If you’re the owner of a business with an online presence, it’s likely that you have at some point in the recent past considered whether you and your website would benefit from a high performance content delivery network solution. In this article, we’ll take a look over the most important and top CDN services that potential content delivery network customers should consider and take into account when searching for their ideal content delivery network provider.
Given the huge popularity of content delivery networks and the rise of the CDN market in the past decade, there are many reputable content delivery network providers available. Most large companies with a web presence have taken advantage of CDN providers such as Akamai, Cloudflare, ChinaCache, CDNetworks, Verizon, Fastly, Level 3 and CDN77, meaning there is a huge amount of expertise available for those looking for top CDN services. In no particular order, here at the top CDN services that you should be looking for when selecting your ideal CDN provider:
How Does a Content Delivery Network Work?
When considering the top CDN services for your organisation, it’s first important to understand exactly how a content delivery network actually operates.
When you sign up for a content delivery network, you upload your files to the CDN servers. A content delivery network then caches that data to their points of presence (PoPs) all over the globe. Depending on the reach, specialisation and size of the content delivery provider, those points of presence could span a country, continent or the world. Identical copies of your website’s data are stored on these points of presence, providing many redundant backups of the data.
When an end user or customer visits your site and clicks on a download link to a file that is hosted by a CDN provider, they are redirected to the version of the file that is located on the server that is geographically closest to them. The benefits of this are twofold: firstly, the shorter geographical distance that the request has to travel across results in a lower latency connection. This means the server responds to the request much more quickly. Secondly, as there are multiple points of presence hosting the file across different regions, it is likely that there will be less traffic being served by that PoP. This should result in greater bandwidth being available for the end user, increasing download speeds.
Static delivery services are the bread and butter of content delivery network providers. The original and most popular content delivery service, static delivery enables the swift delivery of large static data, such as software installation files or game updates.
Static delivery content delivery network services are ideal for software companies or game producers. It allows them to cache their data across a content delivery network’s points of presence, giving their end users access at high performance no matter where they are.
Dynamic Site Acceleration
One of the top CDN services being sought out by modern companies with an online presence is dynamic site acceleration. Compared to static delivery acceleration, that optimises the delivery or large data files, dynamic site acceleration works by optimising data that is constantly changing.
This kind of content delivery network service is ideal for today’s internet. As more and more people access social media website, ecommerce sites and ultra personalised web services, we are seeing more and more demand for dynamic site acceleration.
There are four key technologies that come into play when content delivery networks optimise dynamic data. The first is TCP multiplexing. This technology works because an edge device, such as a content delivery network or application delivery controller (ADC), is capable of TCP multiplexing which is placed on the network between servers or points of presence and the end user. This means data is offloaded from the origin server (where the original data was held), leading to accelerated delivery. The reason for this is that, usually, a request for data must be sent all the way to the origin server. However, TCP multiplexing eliminates this need, allowing the request to stop at the multiplexer where it is then relayed on to the origin server. This offloads application and database servers, which are slower and more expensive to use compared to ADCs or CDNs.
The second technology for optimising dynamic sites is dynamic cache control. This works by increasing the cache-hit ratio of a website. The cache-hit ratio of a site determines the rate between requests served by the cache and those served by the normal server. By using options such as cookie-based cache control, dynamic sites can personalise content based on location and other user preferences, serving only data that is right for them, reducing unnecessary additional downloads.
The third technology is prefetching, which allows uncacheable data to be stored on an edge device so that latency can be reduced and the delivery of the data is not delayed. The final option for dynamic site acceleration is route optimisation. This involves the optimisation of the route that traffic takes between end users and the different content delivery network origin servers in order to reduce latency. The works by having the CDN measure many different network paths and dynamically selecting the quickest route with the lowest latency.
In order to boast a list of top CDN services, many content delivery network providers now offer mobile optimisation services. These services are key thanks to the huge rise in use of mobile networks, driven by the adoption of cheap mobile enabled devices in the developing world.
In order to optimise data flow across a mobile network, many technologies much be implemented to overcome the differences that exist between mobile networks and traditional networks.
Mobile networks generally have lower bandwidth, higher latency and higher packet loss compared to land-based networks. As such, data is often compressed before being delivered across mobile content content delivery networks. This type of optimisation is perfect for files that can be large insize, such as rich image files. For video, services such as video transcoding and adaptive bitrate services can dynamically change the quality of video streams so that they can be reduced in size, allowing easy delivery over low bandwidth connections.
Video Delivery and Optimisation
One of the biggest drivers that has helped fuel the rise in internet use over the past decade is the consumption of online video. Whether it be the live streaming of sports events or on demand viewing services such as Netflix, Hulu and Amazon Prime video, any CDN provider that is serious about delivery will have a video delivery and optimisation service, making this come as a vital component of our top CDN services list.
Content delivery networks optimise the delivery of video in many ways. This can include dedicated HTML5 players that are lightweight and incorporate digital rights management technologies to the optimisation of video streams themselves. As mentioned in the mobile content delivery network section, this includes many technologies. One such technology is video transcoding, which involves the decompressing and recompressing of video before delivery to ensure it is properly compressed and as small a file size as possible. In addition to this, adaptive bitrate technologies can help with video delivery. This works by dynamically reducing the bitrate, and thus quality, of a video as network bandwidth becomes scarce. Bitrates can then be increased if and when more bandwidth is available so that the video quality can be improved if there is leeway in the network.
As more and more websites fall victim to distributed denial of service (DDoS) attacks, high performance DDoS protection is become more important on list of top CDN services.
DDoS attacks occur when a malicious attacker utilises a distributed network of computers (often leveraged as the result of viruses or malware infecting the distributed machines) to bombard a website with requests for data. This causes the network that the site is hosted on to become jammed and ultimately crash.
There are many ways in which a content delivery network provider can protect against this kind of attack. Firstly, CDNs are able to easily scale upwards if a website requires more bandwidth. Given the global nature of CDNs, they often have spare capacity across points of presence around the world, and this can be called upon if required.
Secondly, content delivery networks use more proactive methods to protect against DDoS attacks. Trusted locations and IP address can be specified so that unknown requests or requests from known compromised IPs is restricted. Furthermore, advanced analytics and monitoring capabilities ensure that webmasters can be immediately notified of suspicious activity.
Content Delivery Network Reach
Finally, on of the most important top CDN services revolves around the reach and size of a content delivery network provider’s network. Depending on where you are serving your data and how many customers you have, you’ll want to select a content delivery network provider that offers points of presence in your target locations. Some larger CDN providers such as Akamai, Level 3 and Cloudflare specialise in offering high performance content delivery network solutions to customers all around the globe with PoPs in every region, while smaller CDNs, such as ChinaCache, specialise in optimising traffic in specific regions.
As you can see, there are many top CDN services that you should take into account when selecting your ideal content delivery network provider. If you consider this list carefully, you should be able to accelerate your data to your customers no matter where they are.