Blockchain Mutability: Challenges and Proposed Solutions

Blockchain's evolution during the past decade is astonishing: from bitcoin to over 2.000 altcoins, and decentralised electronic payments transactions programmable by smart contracts complex tokens governed organisations. While new generation of blockchain applications still evolving, blockchain's technical characteristics are also advancing. Yet, immutability, a hitherto indisputable highly advertised property according which data cannot be edited nor deleted, remains cornerstone security. Nevertheless, immutability being called into question lately in light erasing requirements imposed GDPR's “ Right Forgotten (RtbF) ” provision. As RtbF obliges editable order restricted content redactions, modifications or deletions applied when requested, blockchains compliance with regulation indeed challenging, if not impracticable. Towards resolving this contradiction, various methods techniques for mutable have been proposed satisfy regulatory while preserving blockchains’ To end, work aims provide comprehensive review on state-of-the-art research approaches, workarounds advanced cryptographic that put forward resolve conflict discuss their potentials, constraints limitations wild either permissioned permissionless blockchains.