ECIP-1049 Keccak256
ECIP-1049 proposed changing ETC's mining algorithm from Ethash/Etchash to Keccak256 (SHA-3). After three years of discussion and four Core Devs Calls, the proposal was withdrawn due to lack of consensus and risk of a contentious chain split.
ECIP-1049 Keccak256 Mining Algorithm Change
ECIP Status: Withdrawn
Discussion Period: 2019–2022
Outcome: Proposal withdrawn — no consensus reached
Overview
ECIP-1049 proposed replacing ETC's Ethash/Etchash proof-of-work algorithm with Keccak256 (SHA-3). Proponents argued it would improve ASIC resistance and align ETC with a NIST-standardized hash function. Opponents raised concerns about a contentious chain split between GPU miners on Etchash and FPGA/ASIC miners on SHA-3, disruption to the existing mining ecosystem, and violation of the ECIP process requirements for rough consensus.
Timeline
- 2019: ECIP-1049 submitted, entered Last Call status
- September 11, 2020: Core Devs Call 13 — mining algorithm review alongside ECIP-1043 (Fixed DAG) and ECIP-1099 (Calibrate Epoch Duration)
- September 25, 2020: Core Devs Call 14 — 51% attack solutions discussed in the wake of multiple attacks. ECIP-1099 moved toward acceptance
- October 2, 2020: Core Devs Call 15 — dedicated ECIP-1049 breakout session. Consensus was not present due to many unanswered questions
- November 28, 2020: Thanos upgrade activated with ECIP-1099 (Etchash) instead
- February 21, 2022: Core Devs Call 22 — proposed rejection. Original champion stepped down; Bob Summerwill became new champion. Agreed the proposal needed a material rewrite
- 2022: ECIP-1049 withdrawn. The Etchash mining ecosystem was preserved
Key Issues
- Contentious chain split risk — GPU miners on Etchash would not automatically migrate to Keccak256 hardware. A forced algorithm change risked splitting the network
- Existing ecosystem disruption — Miners had invested in Etchash-compatible hardware. ECIP-1099 (Thanos) had already addressed the DAG size concern
- ECIP process compliance — Opposition argued the proposal lacked the rough consensus required by ECIP-1000 for protocol changes
- Alternative adopted — ECIP-1099 (Etchash) was accepted and activated at block 11,700,000, resolving the GPU mining accessibility concern that motivated ECIP-1049