People have been viewing videos online since the birth of the Internet. But whereas the original videos were the size of a postage stamp, nowadays online films are often HD quality or even higher (4K). Not only is the quality of videos improving, but more and more people are watching online. Just look at viewer numbers for videos and other programmes on YouTube, iPlayer, RTL XL and other paid services such as iTunes and Netflix. In this post I talk about what these services mean for a network, and what past experience has taught us in this regard.
Online video: SURFnet is ready for the World Cup (and the Tour de France!)
With all these viewers and various sources, you can probably imagine how hard the SURFnet (and other) networks need to work to get all the data to viewers. Last February saw the Winter Olympics in Russia. The graph below clearly shows the enormous spike in data transferred from the NPO Dutch Public Broadcasters to SURFnet in this period during key events such as Dutch skating. On average, streaming video uses 5Mbit/s of data – meaning this is the amount of data per viewer that needs to be transported by the network.
Various events in the past have shown that the time of day when they take place greatly influences people’s viewing behaviour. Events that happen during the day (such as skating) are clearly evident in the network traffic statistics. For the first time, however, the World Cup football (which is played in the evening) can now also clearly be seen in the traffic data, despite the fact that previously, evening viewing was barely evident (if at all) in the measurements taken. Something therefore seems to be changing in the way people watch television programmes.
Figure 2: Network traffic during the football World Cup The figure above shows network traffic from the Dutch Public Broadcasters to SURFnet. The overview starts on Friday 13 June, when the Dutch team played their first match against Spain, and also clearly shows the match against Australia on Wednesday 18 June.
How have things changed?
The move from a tiny format to HD quality and the rise in the number of online viewers has resulted in increased bandwidth requirements for video data. Some time ago, a modest number of Dutch viewers watched Prince Claus’ funeral and the fall of the Cabinet in October 2002 (two events that took place simultaneously), creating around 700 MB of data traffic. Today, the Australia-Netherlands match (outside office hours) generated around 30 GB of data.
Figure 3: Prince Claus’ funeral and the fall of the Cabinet The increase in both the number of viewers and the quality of online video has resulted in a significant rise in the quantity of data processed daily by SURFnet. A service such as YouTube generates a daily data stream of around 10~15 Gbit/s, and is growing steadily.
Figure 4: Growth in Google traffic 2010-2014
And what is SURF doing with this information?
To ensure that everybody who wants to watch online can continue to do so, we have made a number of adjustments to our network in recent times. The capacity of the connection between the Dutch Public Broadcasters and SURFnet has been increased, as has that of the connection with AMS-IX. A separate connection has been set up between SURFnet and Google to ensure that we can accurately measure data volumes and increase capacity easily when the need arises. During peak times, such as now during the World Cup, the network will be monitored more closely to enable us to adjust routing and distribute traffic across the available bandwidth if necessary.
These adjustments make SURFnet not only World Cup-proof, but also prepare us for the ‘traffic congestion’ expected on the network during the Tour de France this summer. We wish you all an enjoyable summer of sport!