Many years ago, a friend of mine calculated how much it would cost +to store the sound of all phone calls in Norway, and came up with the +cost of around 20 million NOK (2.4 mill EUR) for all the calls in a +year. I got curious and wondered what the same calculation would look +like today. To do so one need an idea of how much data storage is +needed for each minute of sound, how many minutes all the calls in +Norway sums up to, and the cost of data storage.
+ +The 2005 numbers are from +digi.no, +the 2012 numbers are from +a +NKOM report, and I got the 2013 numbers after asking NKOM via +email. I was told the numbers for 2014 will be presented May 20th, +and decided not to wait for those, as I doubt they will be very +different from the numbers from 2013.
+ +The amount of data storage per minute sound depend on the wanted +quality, and for phone calls it is generally believed that 8 Kbit/s is +enough. See for example a +summary +on voice quality from Cisco for some alternatives. 8 Kbit/s is 60 +Kbytes/min, and this can be multiplied with the number of call minutes +to get the storage requirements.
+ +Storage prices varies a lot, depending on speed, backup strategies, +availability requirements etc. But a simple way to calculate can be +to use the price of a TiB-disk (around 1000 NOK / 120 EUR) and double +it to take space, power and redundancy into account. It could be much +higher with high speed and good redundancy requirements.
+ +But back to the question, What would it cost to store all phone +calls in Norway? Not much. Here is a small table showing the +estimated cost, which is within the budget constraint of most medium +and large organisations:
+ +| Year | Call minutes | Size | Price in NOK / EUR |
|---|---|---|---|
| 2005 | 24 000 000 000 | 1.3 PiB | 3 mill / 358 000 |
| 2012 | 18 000 000 000 | 1.0 PiB | 2.2 mill / 262 000 |
| 2013 | 17 000 000 000 | 950 TiB | 2.1 mill / 250 000 |
This is the cost of buying the storage. Maintenance need to be +taken into account too, but calculating that is left as an exercise +for the reader. But it is obvious to me from those numbers that +recording the sound of all phone calls in Norway is not going to be +stopped because it is too expensive. I wonder if someone already is +collecting the data?
+