DVB-CSA-1 vs DVB-CSA-2

I need some help from mpeg2-ts DVB and broadcasting experts. Can someone tell me what is t开发者_如何学Che difference between those algorithms in common.

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They are two different content scrambling schemes. AFAIK, CSA2 has never been used much (at all?) in distribution. Contribution is a different story, and CSA2 has seen wider adoption there.

Scrambling algorithms for broadcast are defined in TS 100 289 and for IPTV in TS 103 127. It seems that CSA3 is now used in some IPTV deployments, too.

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There are 64 bits control words in either of them. However, in the CSA1 only 48 bits are used for transferring the uniq key data and other 16 bits can be calculated based on them.

CSA2 has all 64 bits as a key.

That makes CSA2 more secure as a key is longer.