Content Delivery Networks – What They Are and Why They’re Powerful

One of the most important factors impacting web performance has nothing to do with the technology itself, but where it sits on the planet. Greater physical distance between a server and client (the user) can slow down the rate and reliability of even the most performant service. Content delivery networks (CDNs), seek to solve this issue by getting the servers closer to the site visitors, customizing the delivery to suit individualized worldwide position. A content delivery network is a vast collection of cache servers that leverage geolocation to determine where a website’s content is delivered from.

Reducing latency is one of the most important reasons that content delivery networks are used. The closer the data is to the end-user, the faster it can be sent to them. For services that depend on real-time, continuous data on a global scale, CDNs are critical.

Content delivery networks are also characterized by their inherent redundancy. There are multiple copies of a website’s files placed around the world. CDNs will often have thousands of different physical machines serving content to clients, which allows this process to be both efficient and reliable – regardless of whether there are bandwidth constraints or it is a peak time for the service.

For some types of services, CDNs are now considered a crucial part of infrastructure, being adopted broadly by most top-tier online services. For those who want to deliver large quantities of internet protocol TV (IPTV), video, or audio, like Netflix, it can be considered a best practice. However, CDNs are not limited to those scenarios; they are sometimes used to accelerate the transmission of general webpages, whether dynamic or static, by internet service providers (ISPs).

The result of this technological approach is that packet loss is minimized, bandwidth is optimized, and speed is improved. Timeouts, jitter, and latency are all decreased. In turn, user experience (UX) is enhanced. Security is strengthened too: if there is a breach or malware that occurs at one web intersection, the content that is within the CDN will still be available to a portion of the general user population.

CDNs: One way Netflix and Google establish competitive advantage

When streaming video is discussed, ISPs are at the top of that conversation. However, the CDN has become fundamental to the way that Netflix makes its way quickly and unproblematically to people’s devices. The importance of this technology is what has been prompting Netflix and Google to put large amounts of money into developing their CDNs.

Mark Hoelzel of Business Insider notes that CDNs are appreciated because they are designed to deliver large pieces of content through various ISPs, and to diverse nations and regions, via web infrastructure. Hoelzel summarizes, “CDNs take the guess-work and heavy lifting out of the complex task of delivering video, in a reliable manner, to millions of viewers served by a variety of different ISPs.”[i]

Currently, “behemoth” content providers Netflix and Google are quickly building upon their own content delivery networks, which are respectively called Open Connect and Global Cache. In so doing, the two Silicon Valley powerhouses are fulfilling content requests of web users at a higher performance level, while exerting more control over the flow of traffic.

Basics on Open Connect and Global Cache

The objective of the Netflix’s Open Connect content distribution network, according to the video service’s own message, is to deliver better user experience to subscribers – which number more than 86 million.[ii] Netflix notes in its description that the corporation works to contain large chunks of traffic locally; additionally, the interconnected sites are all open-peered.[iii]

Google’s Global Cache (GGC) allows organizations to limit the expenses of network infrastructure, specifically related to content from YouTube and Google, by serving the content internally. GGC is a cluster of servers that are implemented within the datacenter of a private firm, with management performed remotely by Google.[iv]

The Netflix CDN exemplifying the power of the CDN

Netflix was in the news in 2016 for transitioning from its own data centers to the cloud – a similar massive-enterprise “all-in with cloud” story as General Electric. The transition is an incredible statement, really, when you consider that Netflix streams content that it hosts to users. The story about Netflix was a bit misleading because it seemed to suggest the company was comprehensively outsourcing its machines. Some of them were remaining in-house, including its CDN.

To understand Netflix’s CDN, it helps to know what it does not do. It does not serve data to users of its billing app, customer service portal, the frontend of the app (i.e., not the content), or the algorithm that personalizes suggestions – all of which is now served from their public cloud.

Netflix’s Open Connect CDN serves the movie and television content that Netflix provides to users. As with all CDNs, the content exists as multiple copies across Netflix’s global distribution of Open Connect hardware, which is made up of actual physical appliances that contain as much as 280 terabytes of storage in each location.

Mark Barry of analytics firm Aberdeen describes how these appliances deliver movies to households: “Any time someone clicks on a movie title, one of these boxes, situated at a proximate location, will begin serving that content.”[v]

The CDN appliances, particularly the American-based ones, are physically stored within what’s called internet exchange points (IXPs). IXPs are network access points where major networks are connected and where traffic is passed between providers. It enables the exchange of web traffic without the use of upstream third-parties.

An IXP generally needs more Open Connect CDN machines than would be required in an ISP data center. However, the IXPs are more cost-effective and provide high performance. By integrating a CDN and having greater control over how the content is delivered, Netflix – like Google – has leveraged this potent technology for faster and smarter growth.

CDN as a useful technology for websites

Huge enterprises such as Netflix and Google are of course not the only organizations that are benefiting from the use of CDNs. This technology is valuable to any global business. A CDN improves website performance by giving you access to data centers that are physically closer to end-users. This approach reduces the amount of packet loss, latency, jitter, and timeouts; and it makes the use of bandwidth more efficient. Meanwhile, you get better user experience and security.

Do you want to deliver content to your customers faster and more reliably through a content distribution network? Are you interested in offering that “Netflix advantage” to your customers? At Atlantic.Net, we can help you better meet the needs of your customers with our industry-leading service levels, including Managed HIPAA Hosting for the Healthcare Industry – backed by a 100% Uptime SLA. Contact us today!

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[i] http://www.businessinsider.com/netflix-and-google-are-building-out-their-own-content-distribution-networks-2014-6

[ii] http://money.cnn.com/2016/10/17/technology/netflix-earnings-subscribers/

[iii] https://openconnect.netflix.com/en/

[iv] https://isp.google.com/iwantggc

[v] http://www.aberdeenessentials.com/techpro-essentials/how-the-netflix-cdn-demonstrates-the-importance-of-content-delivery/