What exactly is a CDN? A content delivery network or content distribution network (CDN) is a system of computers containing copies of data, placed at various points in a network so as to maximize bandwidth for access to the data from clients throughout the network. A client accesses a copy of the data near to the client, as opposed to all clients accessing the same central server, so as to avoid bottleneck near that server.
Content types include web objects, downloadable objects (media files, software, documents), applications, real time media streams, and other components of internet delivery (DNS, routes, and database queries).
Well you might ask how this technology will help speed up my site? Think about it this way, if my sites server is in Los Angeles and you are in Tokyo, it will take a few extra seconds for the data to travel the distance, but with a CDN, data is stored on several servers on earth, sending you my site from an Asian network cutting valuable seconds off load time. Yes, these services cost money, but not much, and are worth their weight in happy visitors.
CDN Service Providors
There are several CDN providers online and I’ll give you a few of the best. Amazon Cloudfront, Level 3, Akamai Technologies, Internap, PEER1 and Limelight.
Hey, you like free? Try this on for size then: Coral CDN!
The Benefits of a CDN
CDN technologies give more control of asset delivery and network load. They can optimize capacity per customer, provide views of real-time load and statistics, reveal which assets are popular, show active regions and report exact viewing details to the customers. These usage details are an important feature that a CDN provider must provide, since the usage logs are no longer available at the content source server after it has been plugged into the CDN, because the connections of end-users are now served by the CDN edges instead of the content source.
In short, a CDN allows you to target your content towards visitors that are far away from you. (eg. over seas) You also get analytics of usage by region of the world which will help you target content towards your most loyal visitors.
How CDN’s Work
CDN nodes are usually deployed in multiple locations, often over multiple backbones. These nodes cooperate with each other to satisfy requests for content by end users, transparently moving content to optimize the delivery process. Optimization can take the form of reducing bandwidth costs, improving end-user performance (reducing page load times and user experience), or increasing global availability of content.
The number of nodes and servers making up CDN varies, depending on the architecture, some reaching thousands of nodes with tens of thousands of servers on many remote PoPs. Others build a global network and have a small number of geographical PoPs.
Requests for content are typically algorithmically directed to nodes that are optimal in some way. When optimizing for performance, locations that are best for serving content to the user may be chosen. This may be measured by choosing locations that are the fewest hops, the fewest number of network seconds away from the requesting client, or the highest availability in terms of server performance (both current and historical), so as to optimize delivery across local networks. When optimizing for cost, locations that are least expensive may be chosen instead.
In an optimal scenario, these two goals tend to align, as servers that are close to the end user at the edge of the network may have an advantage in performance or cost. The Edge Network is grown outward from the origin/s by further acquiring (via purchase, peering, or exchange) co-locations facilities, bandwidth and servers.
Make your visitors happy with short Web page load times, reliable service and high-quality audio and video downloads. One of the many benefits of the Edge Caching content delivery network is it accelerates your content delivery, giving your visitors an enjoyable experience on your site.
If you use a CDN or are in the market for one, let us know who you have chosen and why. I look forward to hearing what you guys have to say.