# 105 TB in 250 Trains

Teltarif recently published an interesting number on the use of Internet access over Wifi in the 250 high speed trains in Germany: 105 Terabytes per month (see here and here in German). An impressive number (at first). So what’s the average data throughput per train then?

Let’s do the maths:

105 TB = 105.000 GB = 105.000.000 MB

Let’s divide that number by 250 trains and 30 days and we get:

14.000 MB transferred per train per day.

Let’s further divide that number by, let’s say 15 hours and not by 24 hours as trains are not running around the clock and to account for some peak usage and we get:

933 MB per hour per train.

To get down to the average throughput the number needs to be divided by 60 minutes and by 60 seconds and then multiplied by 8 to get to the Mbit/s value which is:

2.07 Mbit/s

There we go the average throughput on a train is around 2 Mbit/s according to the input above. I wouldn’t be surprised if usage on the train is quite evenly distributed as people have time on their hands or, like me, use the train because they can work.

I was actually quite surprised by that number because there hundreds of people on each train so that number seems quite low. True, Wifi access is only free for 1st class passengers today, but still the number seems rather low. So perhaps there’s something wrong with my input or perhaps I made an error in my calculation!? If you spot it, please let me know.

Should you be aware of other reports about Internet usage on trains in other countries that give interesting number, please also consider leaving a comment.