--- /dev/null
+<?xml version="1.0" encoding="ISO-8859-1"?>
+<rss version='2.0' xmlns:lj='http://www.livejournal.org/rss/lj/1.0/'>
+ <channel>
+ <title>Petter Reinholdtsen - Entries from May 2015</title>
+ <description>Entries from May 2015</description>
+ <link>http://people.skolelinux.org/pere/blog/</link>
+
+
+ <item>
+ <title>What would it cost to store all phone calls in Norway?</title>
+ <link>http://people.skolelinux.org/pere/blog/What_would_it_cost_to_store_all_phone_calls_in_Norway_.html</link>
+ <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/What_would_it_cost_to_store_all_phone_calls_in_Norway_.html</guid>
+ <pubDate>Fri, 1 May 2015 19:30:00 +0200</pubDate>
+ <description><p>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.</p>
+
+<p>The 2005 numbers are from
+<a href="http://www.digi.no/analyser/2005/10/04/vi-prater-stadig-mindre-i-roret">digi.no</a>,
+the 2012 numbers are from
+<a href="http://www.nkom.no/aktuelt/nyheter/fortsatt-vekst-i-det-norske-ekommarkedet">a
+NKOM report</a>, 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.</p>
+
+<p>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
+<a href="http://www.cisco.com/c/en/us/support/docs/voice/voice-quality/7934-bwidth-consume.html#topic1">summary
+on voice quality from Cisco</a> 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.</p>
+
+<p>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. It could be much higher with
+high speed and good redundancy requirements.</p>
+
+<p>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:</p>
+
+<table border="1">
+<tr><th>Year</th><th>Call minutes</th><th>Size</th><th>Price in NOK / EUR</th></tr>
+<tr><td>2005</td><td align="right">24 000 000 000</td><td align="right">1.3 PiB</td><td align="right">3 mill / 358 000</td></tr>
+<tr><td>2012</td><td align="right">18 000 000 000</td><td align="right">1.0 PiB</td><td align="right">2.2 mill / 262 000</td></tr>
+<tr><td>2013</td><td align="right">17 000 000 000</td><td align="right">950 TiB</td><td align="right">2.1 mill/ 250 000</td></tr>
+</table>
+
+<p>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?</p>
+</description>
+ </item>
+
+ </channel>
+</rss>
--- /dev/null
+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
+ "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
+<html xmlns="http://www.w3.org/1999/xhtml" dir="ltr">
+ <head>
+ <meta http-equiv="Content-Type" content="text/html;charset=utf-8" />
+ <title>Petter Reinholdtsen: entries from May 2015</title>
+ <link rel="stylesheet" type="text/css" media="screen" href="http://people.skolelinux.org/pere/blog/style.css" />
+ <link rel="stylesheet" type="text/css" media="screen" href="http://people.skolelinux.org/pere/blog/vim.css" />
+ <link rel="alternate" title="RSS Feed" href="05.rss" type="application/rss+xml" />
+ </head>
+ <body>
+ <!-- XML FEED -->
+ <div class="title">
+ <h1>
+ <a href="http://people.skolelinux.org/pere/blog/">Petter Reinholdtsen</a>
+
+ </h1>
+
+</div>
+
+
+ <h3>Entries from May 2015.</h3>
+
+ <div class="entry">
+ <div class="title">
+ <a href="http://people.skolelinux.org/pere/blog/What_would_it_cost_to_store_all_phone_calls_in_Norway_.html">What would it cost to store all phone calls in Norway?</a>
+ </div>
+ <div class="date">
+ 1st May 2015
+ </div>
+ <div class="body">
+ <p>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.</p>
+
+<p>The 2005 numbers are from
+<a href="http://www.digi.no/analyser/2005/10/04/vi-prater-stadig-mindre-i-roret">digi.no</a>,
+the 2012 numbers are from
+<a href="http://www.nkom.no/aktuelt/nyheter/fortsatt-vekst-i-det-norske-ekommarkedet">a
+NKOM report</a>, 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.</p>
+
+<p>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
+<a href="http://www.cisco.com/c/en/us/support/docs/voice/voice-quality/7934-bwidth-consume.html#topic1">summary
+on voice quality from Cisco</a> 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.</p>
+
+<p>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. It could be much higher with
+high speed and good redundancy requirements.</p>
+
+<p>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:</p>
+
+<table border="1">
+<tr><th>Year</th><th>Call minutes</th><th>Size</th><th>Price in NOK / EUR</th></tr>
+<tr><td>2005</td><td align="right">24 000 000 000</td><td align="right">1.3 PiB</td><td align="right">3 mill / 358 000</td></tr>
+<tr><td>2012</td><td align="right">18 000 000 000</td><td align="right">1.0 PiB</td><td align="right">2.2 mill / 262 000</td></tr>
+<tr><td>2013</td><td align="right">17 000 000 000</td><td align="right">950 TiB</td><td align="right">2.1 mill/ 250 000</td></tr>
+</table>
+
+<p>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?</p>
+
+ </div>
+ <div class="tags">
+
+
+ Tags: <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/personvern">personvern</a>, <a href="http://people.skolelinux.org/pere/blog/tags/surveillance">surveillance</a>.
+
+
+ </div>
+ </div>
+ <div class="padding"></div>
+
+ <p style="text-align: right;"><a href="05.rss"><img src="http://people.skolelinux.org/pere/blog/xml.gif" alt="RSS Feed" width="36" height="14" /></a></p>
+ <div id="sidebar">
+
+
+
+<h2>Archive</h2>
+<ul>
+
+<li>2015
+<ul>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2015/01/">January (7)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2015/02/">February (6)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2015/03/">March (1)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2015/04/">April (4)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2015/05/">May (1)</a></li>
+
+</ul></li>
+
+<li>2014
+<ul>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2014/01/">January (2)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2014/02/">February (3)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2014/03/">March (8)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2014/04/">April (7)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2014/05/">May (1)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2014/06/">June (2)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2014/07/">July (2)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2014/08/">August (2)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2014/09/">September (5)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2014/10/">October (6)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2014/11/">November (3)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2014/12/">December (5)</a></li>
+
+</ul></li>
+
+<li>2013
+<ul>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2013/01/">January (11)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2013/02/">February (9)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2013/03/">March (9)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2013/04/">April (6)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2013/05/">May (9)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2013/06/">June (10)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2013/07/">July (7)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2013/08/">August (3)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2013/09/">September (5)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2013/10/">October (7)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2013/11/">November (9)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2013/12/">December (3)</a></li>
+
+</ul></li>
+
+<li>2012
+<ul>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2012/01/">January (7)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2012/02/">February (10)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2012/03/">March (17)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2012/04/">April (12)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2012/05/">May (12)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2012/06/">June (20)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2012/07/">July (17)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2012/08/">August (6)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2012/09/">September (9)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2012/10/">October (17)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2012/11/">November (10)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2012/12/">December (7)</a></li>
+
+</ul></li>
+
+<li>2011
+<ul>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2011/01/">January (16)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2011/02/">February (6)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2011/03/">March (6)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2011/04/">April (7)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2011/05/">May (3)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2011/06/">June (2)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2011/07/">July (7)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2011/08/">August (6)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2011/09/">September (4)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2011/10/">October (2)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2011/11/">November (3)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2011/12/">December (1)</a></li>
+
+</ul></li>
+
+<li>2010
+<ul>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2010/01/">January (2)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2010/02/">February (1)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2010/03/">March (3)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2010/04/">April (3)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2010/05/">May (9)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2010/06/">June (14)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2010/07/">July (12)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2010/08/">August (13)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2010/09/">September (7)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2010/10/">October (9)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2010/11/">November (13)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2010/12/">December (12)</a></li>
+
+</ul></li>
+
+<li>2009
+<ul>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2009/01/">January (8)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2009/02/">February (8)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2009/03/">March (12)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2009/04/">April (10)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2009/05/">May (9)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2009/06/">June (3)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2009/07/">July (4)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2009/08/">August (3)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2009/09/">September (1)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2009/10/">October (2)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2009/11/">November (3)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2009/12/">December (3)</a></li>
+
+</ul></li>
+
+<li>2008
+<ul>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2008/11/">November (5)</a></li>
+
+<li><a href="http://people.skolelinux.org/pere/blog/archive/2008/12/">December (7)</a></li>
+
+</ul></li>
+
+</ul>
+
+
+
+<h2>Tags</h2>
+<ul>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/3d-printer">3d-printer (13)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/amiga">amiga (1)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/aros">aros (1)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/bankid">bankid (4)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/bitcoin">bitcoin (8)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/bootsystem">bootsystem (15)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/bsa">bsa (2)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/chrpath">chrpath (2)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/debian">debian (109)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu (153)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/digistan">digistan (10)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/dld">dld (15)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/docbook">docbook (13)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/drivstoffpriser">drivstoffpriser (4)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/english">english (276)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/fiksgatami">fiksgatami (23)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/fildeling">fildeling (12)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/freeculture">freeculture (15)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/freedombox">freedombox (9)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/frikanalen">frikanalen (14)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/intervju">intervju (42)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/isenkram">isenkram (10)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/kart">kart (19)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/ldap">ldap (9)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/lenker">lenker (8)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/lsdvd">lsdvd (2)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/ltsp">ltsp (1)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/mesh network">mesh network (8)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/multimedia">multimedia (32)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/norsk">norsk (260)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug (176)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/offentlig innsyn">offentlig innsyn (16)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/open311">open311 (2)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/opphavsrett">opphavsrett (51)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/personvern">personvern (84)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/raid">raid (1)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/reactos">reactos (1)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/reprap">reprap (11)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/rfid">rfid (3)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/robot">robot (9)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/rss">rss (1)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/ruter">ruter (4)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/scraperwiki">scraperwiki (2)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/sikkerhet">sikkerhet (41)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/sitesummary">sitesummary (4)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/skepsis">skepsis (4)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/standard">standard (46)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/stavekontroll">stavekontroll (3)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/stortinget">stortinget (9)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/surveillance">surveillance (31)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/sysadmin">sysadmin (2)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/usenix">usenix (2)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/valg">valg (8)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/video">video (50)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/vitenskap">vitenskap (4)</a></li>
+
+ <li><a href="http://people.skolelinux.org/pere/blog/tags/web">web (35)</a></li>
+
+</ul>
+
+
+ </div>
+ <p style="text-align: right">
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