ChainLocks: Dash Upgrade To Eliminate 51 Percent Attacks

Payments network Dash (DASH) may soon implement a new, unique network upgrade that will reportedly “eliminate” the threat of a 51% attack from the protocol, once fully implemented

ChainLocks enables transactions to be confirmed and secured as soon as the block has been processed, rather than waiting for six other blocks to be signed first. This makes it nearly impossible for miners to cause chain reorganizations;  blocks, or even chains, that aren’t published can be quickly invalidated by any block confirmed with a ChainLock signature (CLSIG). It was proposed by a member of the network’s core team of developers.

Most Proof-of-Work (PoW) blockchains are vulnerable to 51%, or Consensus attacks; when one miner has more than half of the network’s hashing power. This allows them to take over the network, validating or invalidating any transaction they want. Previous 51% attacks have mostly siphoned tokens into private wallet addresses; some worry they might also be used as a form of industrial sabotage against a rival blockchain.

A PoW network, Dash nonetheless relies on a smaller circle of Masternodes, who must each own at least 1,000 DASH, to verify and validate the chain. Block rewards are split equally between them and miners – the other 10% committed to the network treasury.

Masternodes help to make Dash scalable. In a 24 hour period, the network could process 3m transactions in a recent stress test. It is also Sybil Attack Resistant. Masternodes are incentivized to act honestly with any harm done ultimately affecting the value of their holdings and future earnings.

How Does ChainLocks Make Dash Secure?

ChainLocks works on the Masternode tier, through an application known as Long Living Masternode Quorums (LLMQs). Put simply this improves the network’s voting mechanism by allowing decisions to be taken without individual nodes – nearly 4,900 currently active – having to propagate their own signatures.

With ChainLocks, blocks are confirmed by a quorum; a majority quorum members – the Masternodes – need to agree on which block was the first one. Once more than 60% concur, a CLSIG is then sent out to the rest of the Masternode community, essentially confirming which block was first. The network then rejects other blocks. Secretly mined and processed blocks added to disorganize the network during a 51% attack, are quickly invalidated.

LLMQs are made up of randomly selected Masternodes, making them broadly representative of the total set. If 60% of one quorum agree on what the first block is, this should generally be a majority of the Dash community of validators. Because LLMQs are unique to the Dash network, Dash is reportedly the only network that can implement ChainLocks.

“Pure Proof of Work is only secure against 51% mining attacks if the base assumptions behind mining economics and rationality of participants holds,” said Alexander Block, the Core Developer for Dash Core Group, who developed ChainLocks. “Dash has a unique advantage here, as we can leverage our Sybil attack resistant Masternode network and LLMQs to add more security on top of Proof of Work, which allows us to eliminate the risks of 51% mining attacks.”

Dash is a Decentralized Autonomous Organization (DAO), so ChainLocks will need to be voted upon: Dash Improvement Proposal 8 (DIP8) voting members – the Masternodes – will need to approve before it can be implemented.

Disclaimer: The author is not invested in any cryptocurrencies or tokens mentioned in this article, but holds investments in other digital assets.