Editing DigiCipher 2 (section)

==Technical specifications==
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 [[metadata]], or System Information, where DVB reserves packet identifiers from 16 to 31 for metadata, DigiCipher reserves only packet identifier 8187 for its  [[Program and System Information Protocol|master guide table]] which acts as a ''look-up table'' for all other metadata tables. DigiCipher 2 also extends the MPEG ''program number'' that is assigned for each service in a transport stream with the concept of a [[virtual channel]] number, whereas the DVB system never defined this type of remapping preferring to use a registry of ''network'' identifiers to further differentiate ''program numbers'' from those used in other transport streams.  There are also private non-standard additions to DVB that add virtual channel remapping using ''logical channel numbers''. Also unlike DVB, all text used in descriptors can be compressed using standard [[Huffman coding]] which saves on broadcast bandwidth and loading times. DigiCipher II uses [[Dolby Digital|Dolby Digital AC-3]] audio for all channels, although MPEG-1 Level 2 audio is not supported.<ref name="auto"/>