Multivariable based checkpoints to mitigate the long range attack in proof-of-stake based blockchains

Proof-of-Stake (PoS) is getting popularity among low power computing devices as compared to high power and energy demanded proof-of work (PoW). Among the security issues of PoS, Long range attack is declared as one of the major issue by many researchers. Long range attack allows the minority stakeholders to become majority stakeholders over a long time span and then they can control the whole blockchain protocol to produce the valid alternative history. Checkpointing is referred as solution to mitigate the impact of the long range attack but still for the newly joined users as well as the users those will stay offline for long period of time, checkpointing mechanism needs to be re-evaluated. In this paper we studied the checkpointing mechanism and proposed a new strategy to implement the checkpointing inside the blockchain technology. The proposed strategy is designed specifically to mitigate the long range attack or stake bleeding attack.