Why companies need a content delivery network (CDN)

As the world faces more information overload and as we move increasingly into the cyber world, access to various types of information is becoming increasingly important as bottlenecks continue to plague users.

May 28, 2012

As the world faces more information overload and as we move increasingly into the cyber world, access to various types of information – from anywhere in the world – is becoming increasingly important as bottlenecks continue to plague users, said Jacek Dziembowski, a director of Antfarm, one of the country’s leading video streaming service providers – and the first SA company to design its own content delivery network (CDN).

“As the amount of information being relayed and downloaded around the world – including video content – continues to grow unabated, bottlenecks are becoming increasingly commonplace and company networks, and the Internet itself, are unable to cope with this increasing traffic,” said Dziembowski.”This is why CDNs are becoming vital in the cyber world – and why it is very likely that a lot more will be deployed.”

A CDN is a system of computers containing copies of data placed at various nodes of a network and, when properly designed and implemented, can improve access to the data it caches by increasing access bandwidth and redundancy – and reducing access latency. Data content types often cached in the CDNs include web objects, downloadable objects – media files, software and documents – applications, live streaming video and database queries.

In today’s Internet-focused world, both from a business and personal perspective, serious bottlenecks can occur – even with enterprise networks – and the only way to solve this problem into today’s high-volume information age is to deploy CDNs,” explained Dziembowski.

“One of the strengths of a CDN is it takes users from a centralised distributed content store to a distributed content store, that includes intelligence re-direction technology that transparently routes users to a content store geographically closer to a user, or one that best serves a user – and reduces problems such as buffering delays.

“In the early days of the Internet, when there was not such a large volume of information being sent and received –and downloaded – it didn’t really matter if users accessed just one web server. The Internet was not that over-taxed – like it is now.

“Web users today are demanding faster, higher-quality services from their media hosting companies. The explosion of broadband and the high demand for rich-media content and applications makes quick access and delivery a top priority.

“Nowadays,” he said, “a normal corporate network and server does not scale properly over the Internet and has inherent performance constraints. Scalability needs to be addressed on a national basis and, in some cases, on an international basis – with information flowing from an array of disparate – and distant – points of presence such as New York, to London, to Johannesburg to Sydney.”

Three benefits of a CDN

When it comes to CDNs a user will be directed to the nearest server where the copies of the data are stored as opposed to going to the same main server. The advantage of this system is that, with CDNs, bottlenecks can be avoided at the main server.

There are three main benefits of a CDN, which include faster downloads, content redundancy and data integrity.

When it comes to faster downloads, when a user makes use of a CDN he or she will be directed to the nearest cache server which will have a replica of the exact content of the original server. This will allow visitors to download files from the nearest mirror with the shortest distance.

When it comes to content redundancy sometimes a server may fail and will not function properly. However, with the availability of the CDN, a user need not worry as he will be directed to another server. It also means constant uptime of a user’s web-site or blog.

From data integrity point of view, when a user publishes new content all changes made will immediately be copied to the servers. This guarantees that a user’s files and information are always consistent in every server on the CDN.

Dziembowski said there are numerous international CDNs in operation around the globe, such as Limelight and Akamai, but, when it comes to South African companies, opting for local CDNs is “likely to be the best route”.

“Using a costly international CDN to handle Internet traffic in South Africa will be like hiring an oil tanker to deliver a few litres of oil, when just a small panel van or truck would suffice. So users need to assess what kind of CDN they require – and whether or not a local CDN supplier will suffice. In most instances, South African corporations will arguably find local CDNs will suite both their pockets and their overall efficiency requirements.”