2018 Introduction to Content Delivery Networks (CDN)

Introduction to Content Delivery Networks

With audio commentary

Are CDNs expensive?

What are CDNs?

• Most CDN's offer two payment plans.
• Contracted: Akamai need a minimum committed volume of traffic per month and therefore target larger companies. Prices start from $1000+ per month to millions.
• Pay as you go: A flexible approach for smaller websites with tiered pricing models based on volume.
• Most CDNs will offer you to trial their service for 30 days at little or no cost.
• Recommendation: Organise a trial with multiple CDNs and compare your marketing analytics such as from Google e.g. conversion/abandon rates, video views and viewing length.

• CDNs are used by online media companies to host video content for Live TV (linear) and Video On Demand (VOD).
• Can also be used for serving static content and ecommerce websites.
• Operate nationally and internationally.
• Cost is based on the amount of data consumed, so more popular costs more.
• Offer a quick way to scale your website traffic without having to upgrade your web servers.

Who are the CDN players?

How does a CDN work?

• Large CDNs: More $$$
• Akamai, Limelight, CenturyLink (Level3).
• Medium CDNs: Less $$
• Amazon Cloudfront, Fastly, StackPath, CacheFly.
• Personal Sites: $
• Amazon S3 storage, Cloudflare.

• Makes your website faster by storing a copy of your website content in local caches called regions distributed nationally and internationally.
• CDNs uses mapping to optimally route traffic based on the users location, which is important because the speed of light is fixed and distance increases latency, which affects the customer experience.
• Someone in London would access a UK based CDN region, whereas someone in New York would access US east coast region and Australia, an Asian region all being geographically closest to the customer.

How much faster is a CDN?

Who uses a CDN?

• Typical CDN efficiency averages between 95-99% meaning you need fewer webservers to handle the same volumes of customer traffic.
• If you have a site with personalised content then 70-80% efficiency is possible.
• If you have a static website or blog then over 95% is achievable.
• CDN's offer optimisation with compression and security features to protect your site.
• Improve your sites search engine results.
• Rule of Thumb: Always aim for the highest origin server offload percentage.

• CDN's are used by all large Media companies such as Sky and the BBC, who need to serve millions of customers every day which would be expensive to build and manage themselves.
• Smaller companies and popular blogs can benefit by using a CDN to significantly improve their sites performance and customer experience.
• CDNs can also help protect your website with advanced security features such as Distributed Denial of Service or DDoS attacks and provide SSL encyption.

©2013-18 jeffwebb.com

Twitter @jeffwebbuk

photo credit Nasa / Goddard Space Flight Center / Reto Stöckli