The news of Ethereum Classic (ETC) getting 51% attacked spread like a wildfire just recently. Following this hack, questions began to raise regarding the security levels of various Proof-of-Work (PoW) employing chains. Is there a major flaw floating around in the PoW framework? Is there a workaround that can minimize the damage caused by such attacks? Komodo (KMD) seems to have employed a solution that might help in case of a 51% attack, the Delayed Proof-of-Work (dPoW).

In order to get to know how dPoW improves upon PoW in terms of fighting 51% attacked, BlockPublisher got in touch with the James Lee, the founder and core developer of Komodo. Talking about how dPoW prevents the Komodo ecosystem from 51% attacks, he said:

James: “dPoW changes the consensus rules so that blocks that are notarized cannot be overwritten. Additionally, we change the “confirmations” to return 1, until it is notarized. So exchanges that wait for 2 or more confirmations, are waiting for notarization and once notarized it can’t be undone.”

Talking about the chain getting hacked and blocks becoming unalterable, he said:

James: “Actually it seems the chain is very hard to hack. Only the blocks that are not notarized yet are at risk and if you wait for more than 1 confirmation to be reported, then you know it is safe. This is cross written to the BTC chain so there is a secure external reference. It is really a rather simple change as it only needs one change to the consensus rule.”

Komodo also keeps a backup in the bitcoin chain so essentially, BTC level security is inherited in the ecosystem. Also, all the non-test chains in the Komodo ecosystem use dPoW at their core.

Talking about who does the notarization, he said:

James: “All nodes in the network validate all the proposed notarizations, that makes it decentralized. There are 64 special nodes that are elected each year that wait to get consensus between themselves as to what the blockhash was at a certain height. They then broadcast this tx and all the nodes in the network check to see if it matches what they already have. If so, it becomes the notarized height. If not, it is ignored. So the notarization only acts as reinforcing what is already there. It can’t change the block, it certainly doesn’t make the block, it just broadcasts what the notary nodes came to consensus on by acting as normal nodes.”