DigiCipher 2

<h2 id="technical-specifications">Technical specifications</h2>
<p>DigiCipher II uses QPSK and BPSK at the same time. The primary difference between DigiCipher 2 and DVB lies in how each standard handles SI <a href="/facts/Metadata/qt35z79C">metadata</a>, or System Information, where DVB reserves packet identifiers from 16 to 31 for metadata, DigiCipher reserves only packet identifier 8187 for its  <a href="/facts/Program_and_System_Information_Protocol/XMsmUbzH">master guide table</a> which acts as a <i>look-up table</i> for all other metadata tables. DigiCipher 2 also extends the MPEG <i>program number</i> that is assigned for each service in a transport stream with the concept of a <a href="/facts/Virtual_channel/FdHGAsDQ">virtual channel</a> number, whereas the DVB system never defined this type of remapping preferring to use a registry of <i>network</i> identifiers to further differentiate <i>program numbers</i> from those used in other transport streams.  There are also private non-standard additions to DVB that add virtual channel remapping using <i>logical channel numbers</i>. Also unlike DVB, all text used in descriptors can be compressed using standard <a href="/facts/Huffman_coding/dBgMBz48">Huffman coding</a> which saves on broadcast bandwidth and loading times. DigiCipher II uses <a href="/facts/Dolby_Digital/58JfURnU">Dolby Digital AC-3</a> audio for all channels, although MPEG-1 Level 2 audio is not supported.<a class="footnote-ref" id="fnref:4" href="#fn:4"><sup>4</sup></a>
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<h2 id="external-links">External links</h2>
<ul><li><a href="http://www.coolstf.com/mpeg/">Technical page on digital satellite signals</a></li>
<li><a href="https://web.archive.org/web/20071222145858/http://www.sbe24.org/archive/ltrs2000/c24dec00.asp#eight">Historical Perspective: HBO Implements Scrambling</a></li></ul>

<h2 id="references">References</h2>

<ol>
<li id="fn:1"><p>"Arris closes deal to buy Motorola Home cable and internet biz from Google". engadget.com. 17 April 2013. <a href="https://www.engadget.com/2013/04/17/arris-closes-deal-to-buy-motorola-home-cable-and-internet-biz-fr/" target="_blank">https://www.engadget.com/2013/04/17/arris-closes-deal-to-buy-motorola-home-cable-and-internet-biz-fr/</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li>
<li id="fn:2"><p>"North American MPEG-2 Information". <a href="http://www.coolstf.com/mpeg/#dcii" target="_blank">http://www.coolstf.com/mpeg/#dcii</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li>
<li id="fn:3"><p>"How Do I Crack Satellite and Cable Pay TV? [33c3]". 27 December 2016. <a href="https://media.ccc.de/v/33c3-8127-how_do_i_crack_satellite_and_cable_pay_tv" target="_blank">https://media.ccc.de/v/33c3-8127-how_do_i_crack_satellite_and_cable_pay_tv</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li>
<li id="fn:4"><p>"North American MPEG-2 Information". <a href="http://www.coolstf.com/mpeg/#dcii" target="_blank">http://www.coolstf.com/mpeg/#dcii</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li>
</ol>

DigiCipher 2 open-in-new

DigiCipher 2