Ethereum Classic’s Gambit to Stifle 51% Attacks: Make a MESS – Decrypt

In brief

  • Ethereum Classic has suffered multiple 51% attacks recently.
  • The blockchain has instituted a system called MESS to make attacks prohibitively expensive.
  • ETC Labs CEO discussed the attacks and their solution on the Decrypt Daily podcast.

From July through August, Ethereum Classic suffered three 51% attacks that might have cost the attackers just $3,800 in rented hash power.

So what did Ethereum Classic developers do? They made hash power more expensive.

Ethereum Classic Labs CEO Terry Culver appeared on the Decrypt Daily podcast Monday to explain what ETC Labs and the ETC Core Development Team are calling MESS, or Modified Exponential Subjective Scoring.

“Nodes aren’t designed to distinguish between an attacker chain and an honest mining chain,” he said. “What we’ve done is we’ve created a system by which large reorgs need to have greater difficulty.”

That’s not a problem for legitimate miners, but it’s impractical for malicious actors who would need to show “hash rates sustained over a longer period of time.” If MESS, which was activated on October 10 after successful testing, had been active over the summer, the attacks would have cost $20 million instead of the resale value of a Toyota Corolla, according to an ETC Labs press release.

Hash rate is a measurement of a proof-of-work network’s processing power. Hash rate depends on factors like the mining algorithm, the collective strength of the mining equipment, and user numbers.

In a 51% attack,