I need some help from mpeg2-ts DVB and broadcasting experts. Can someone tell me what is the difference between those algorithms in common.
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.