A Content Delivery Network or Content Supply Network, abbreviated to CDN, is a network of computers that can contain copies of data. Computers on the CDN can demand data they will not already have from other computers on the network that can then be delivered.
If, for example, someone wanted to do a live video transmit from London who have site visitors from around the globe attempting to watch at the same time. This would put a massive load on the streaming server delivering the media, in this example a video stream. Imagine if the viewers of this webcast wanted to watch from Australia, New York, Los Angeles and Japan. The Streaming Servers machine in London would have to broadcast this live movie stream to all those locations which means the video streams would have to 'hop' many times before reaching their destinations on the various continents. This compromises the speed of delivery and sets a massive load on the internet connection being employed by the streaming storage space. In addition, it means the movie stream may experience 'packet corruption' or even 'packet loss' meaning the quality of the video being watched could be affected. This is certainly more relevant if the broadcast is using UDP. If the broadcast is being done over TCP there are more 'load' issues because there is a regular communication between server and client.
Thus the answer to this problem is to have a 'Point of origin' machine that takes the original video stream, which then moves it on to 'Point of presence' servers, or PoPs, around the world after request. So now our streaming server in London does not have to deliver to Quotes, New York, Oregon and Japan as in our above example. A guest that could like to watch the video stream in Australia would use the same online player as people in London to watch it, but now the player is looking at a CDN for a video stream rather than the single streaming machine in London. The CDN would know from the requesting IP address that the request is approaching from Australia and would request the video supply from a 'Point of presence' server nearest to Australia. If that flow would not exist, probably because it has not been requested from this location before, the 'Point of presence' storage space would request it from the 'Origin server'. This specific process would be the same for the viewers in Nyc, Los Angeles and Japan.
The features of this are that the workload to broadcast the video stream is well-balanced across many servers rather than9124 one. The bandwidth is also balanced because all the streams are not coming from the same source, which means more concurrent users can see the video flow with much larger stability. Almost all the CDN servers, the 'Point of origin' and the 'point of existence servers', are strategically put around the world by using an internet backbone making the delivery speed between web servers very fast and reliable.
Articles delivery networks are not bound to only posting the load of video and sound streams. We are able to share images and PDF FORMAT files in the same way. In fact any digital media can be requested over a CDN. Our company is not only confined to media being allocated over a CDN, websites can be cached which obviously makes for faster delivery around the world. Everyone these days for corporate websites which may have millions of hits.
Another benefit of by using a CDN is that once your digital media is on the 'Origin' servers or on the 'Point of presence' servers, it is effectively backed up. If the client requests data from a CDN server that is down, the CDN can produce a request to another server on the network and is still able deliver the media.
The last thing I would like to point out about using Content Delivery Networks is usually that the 'Point of origin' servers can be your company's web servers in your company's server farm. They do not have to be a CDN server. This practice is not recommended by most CDN's as it is more likely to be your company's storage space that is down or experiencing connection issues instead than a CDN storage space. One good thing about having your own 'Point of origin' server is it does allow you to maintain local backups of your content should you need to.