securePrune:Secure block pruning in UTXO based blockchains using Accumulators

In this paper, we propose a secure block pruning scheme called securePrune for reducing the storage space of a full node and synchronization time of bootstrapping nodes joining the Peer-to-Peer (P2P) network in an Unspent Transaction Outputs (UTXO) based blockchain like bitcoin using RSA accumulators. In our scheme, the miners periodically release a snapshot of the blockchain state (UTXO set), the other full nodes in the network, securely prune the historical blocks after attaining the required number of confirmations to the snapshot block. This is achieved through the modification of the block structure by including a representation for the state as an RSA accumulator called accumulator state in the block header and proofs of knowledge for deletion/inclusion of the current block's input/output transactions in the block. The secure and periodic pruning of the old blocks, reduce the synchronization time for a new node joining into the network. The simulation results demonstrate a significant reduction in the storage space of a full node and the bootstrapping cost of the new nodes.