In brief

  • Ethereum Classic Labs has published its "Network Security Plan" following two massive attacks on the blockchain.
  • The developers plan to enhance the cooperation between miners and exchanges and monitor the hash rate more closely.
  • As a long-term measure, ETC may even switch to a completely new consensus algorithm.

Ethereum Classic (ETC) Labs has published a “Network Security Plan” that includes several immediate improvements as well as some long-term measures—going as far as switching to a new consensus algorithm—that could reinforce the blockchain’s security.

This comes just over two weeks after a hacker managed to steal roughly $7.3 million in crypto by conducting two consecutive 51% attacks on the Ethereum Classic blockchain.


A 51% attack is one of the most dangerous challenges a blockchain can face. During such assaults, a single party aims to seize 51%—or more—of a network’s hash power, which would grant the attackers control over the blockchain.

In the short term, ETC Labs plans to go ahead with a “Defensive Mining” plan that would require miners’ cooperation to maintain a more consistent hash rate and adjust it accordingly if needed.

To better detect potential attacks in the future, the developers will also monitor the network more closely to identify anomalies and spikes in hash rate. Another step is close coordination with exchanges that should result in the creation of a whitelist of addresses and confirmation times adjustment.

The ETC Core Team is also currently working on “Permapoint,” an arbitration system that should prevent chain reorganizations caused by 51% attacks when implemented.

A long road ahead

While these fixes will go some way to protecting the network, ETC Labs stated that the blockchain might need much greater fixes, to keep it safe in the long run. These ideas will require community consensus for them to be included in a network upgrade.


The first idea is PirlGuard, a protocol developed and proposed by the Pirl community. This uses so-called “penalty blocks” if a miner proposes a longer and heavier chain. The number of penalty blocks will depend on the number of original blocks that would be reverted if the network reorganizes, effectively doubling the cost of a potential 51% attack.

“Another proposal is enhancing the chain with checkpointing and timestamping. This proposal would employ an external set of parties that securely run an assisting service that guarantees the ledger’s properties and can be relied upon at times when the invested hashing power is low,” ETC Labs added.

Third, Ethereum Classic might even completely switch from its current consensus algorithm Ethash (the same one that Ethereum is using) to a new one—if the community votes for it. Two protocols are currently listed as promising: Ethereum’s Keccak256 and RandomX.

ETC Labs added that while both algorithms are feasible, RandomX might not resolve the issues they are currently facing. Plus, switching to it could also mean that ETC will “step out of the shadow of the Ethereum network and into the shadow of the Monero network.”

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