ASX Replacing CHESS with Blockchain Technology

From TFA:

  Why is ASX replacing CHESS?
  
  While CHESS is a stable and reliable system, it is over 25 years old.

Why yes that sounds like a perfectly valid reason.

  Will ASX give everyone access to the distributed ledger?
  
  No. ASX is not using a publicly available implementation of DLT. ASX will use a permissioned system where ASX clients – that meet the necessary regulatory requirements - are permissioned to access the network, just as they do today when connecting to CHESS.