Ethereum Classic: Proof-of-Work Smart Contracts and Global Censorship Resistance

Published on ethereumclassic.org November 17, 2025

Ethereum Classic is currently the largest proof-of-work smart contract platform. The network operates at roughly 300 terahashes per second (TH/s), according to public hashrate trackers such as 2Miners. This represents approximately 90 to 95 percent of all Ethash or Etchash compatible hashing power across all networks.

This level of mining participation has practical implications. It supports a permissionless environment where individuals and organizations anywhere in the world can participate without identification or prior approval. It also strengthens resistance to censorship because mining hardware and miners themselves are geographically dispersed.

Mining without permission

Anyone with compatible hardware can mine Ethereum Classic. The project’s mining guide at ethereumclassic.org/mining explains how to download mining software, connect to a pool, and begin contributing computational work. No registration, identity verification, or staking commitment is required.

Miners can operate on home computers, small rigs, or professional farms. They may connect through privacy-enhancing routing tools such as TOR, work through international mining pools, or mine solo. The protocol measures only proof-of-work computation and does not track the identity or location of the individual producing it.In contrast, proof-of-stake systems require participants to lock assets in validator nodes. On Ethereum, this means holding 32 ETH to run a validator. Most participants use staking services provided by companies such as Coinbase, Kraken, or Lido, which operate within regulatory jurisdictions. These organizations maintain offices, personnel, and identifiable corporate structures.

Censorship concerns after the Tornado Cash sanctions

When the U.S. Treasury’s Office of Foreign Assets Control sanctioned Tornado Cash in August 2022, the effects were visible across the Ethereum ecosystem. Research from the Federal Reserve Bank of New York documented that a noticeable share of Ethereum blocks began excluding transactions from sanctioned addresses. The report is available here: https://www.newyorkfed.org/research/staff_reports/sr1112

Flashbots, a leading block-building infrastructure provider, added filters for sanctioned addresses. The Block reported that at least 23 percent of Ethereum blocks in October 2022 fell into this category:

After the sanctions announcement, Ethermine, which had been the largest Ethereum mining pool before the Merge, stopped processing Tornado Cash transactions as reported by CryptoSlate

Infrastructure providers also responded. Infura and Alchemy restricted API access to Tornado Cash contracts, and Circle froze USDC held in sanctioned addresses. These actions created cascading effects that influenced validator behavior.

Why this matters for credible neutrality

The response to the Tornado Cash sanctions highlighted an important point about privacy and financial technology. Tools such as mixers and privacy protocols are not inherently criminal. Individuals and organizations use them for many ordinary reasons, including protecting salary information, safeguarding business activity, shielding wallet addresses from public association, or maintaining privacy while transacting in politically sensitive environments. Law enforcement agencies already focus their efforts on the parts of the system where oversight is practical. These are the entry and exit points where digital assets are exchanged for fiat currency, such as centralized exchanges, custodians, and payment processors. These organizations maintain compliance programs, conduct reporting, and cooperate with investigations. Monitoring these regulated entities allows authorities to trace illicit activity without requiring the underlying blockchain to censor or restrict protocol-level transactions.

A blockchain network that maintains integrity at the consensus layer supports this balance. When the network remains neutral, it includes all valid transactions according to the protocol’s rules, regardless of their origin or social interpretation. This approach creates a consistent and predictable execution environment. Participants can rely on the network to process transactions fairly, and regulators still retain the ability to enforce laws at the surrounding on-ramps and off-ramps. Credible neutrality comes from the idea that the network itself should not interpret intent or apply policy but should focus on verifying validity.

How proof-of-work responds differently

Ethereum Classic miners are not organized around validator sets, corporate entities, or identifiable operators. The mining ecosystem follows economic incentives rather than membership requirements. Several characteristics contribute to this:

No identity requirements

Mining does not require formal registration. Participants can redirect their hashrate through different pools or network routes with minimal friction.

Geographic distribution

Miners cluster where electricity costs are favorable. Regions such as Iceland, Kazakhstan, Texas, and parts of China and South America host mining operations because of local energy conditions. This geographic variety spreads risk and reduces the chance that a single government can influence a large percentage of hashrate.

Low switching costs

If a miner encounters regulatory pressure in one jurisdiction, they can move their hashrate to a pool hosted elsewhere. The hardware works on any Etchash chain, and miners frequently switch pools for operational reasons.

Hardware diversity

Ethereum Classic supports mining with both GPUs and ASICs. Etchash was introduced in ECIP-1099 (“Thanos”) to slow the rate at which the DAG file grows. This keeps older 4 GB and 6 GB graphics cards useful for longer periods: https://ecips.ethereumclassic.org/ECIPs/ecip-1099

ASIC manufacturers such as Bitmain, Jasminer, and iPollo all produce miners compatible with Ethereum Classic. Examples include:

  • iPollo V-series: https://ipollo.com/products/v1-mini-etchash
  • Jasminer X16-Q Pro: https://www.jasminer.com/products/x16-q-pro
  • Bitmain Antminer E9 models: https://shop.bitmain.com/products/antminer-e9

Since GPU mining remains common, the network does not rely solely on specialized hardware that could be restricted through export policy.

Current mining landscape

When Ethereum transitioned to proof-of-stake in September 2022, most Ethash miners migrated to Ethereum Classic. Hashrate rose from approximately 65 TH/s to more than 275 TH/s within days, a shift covered by CoinDesk

Today, miners distribute their hashrate across several pools such as:

2Miners (https://2miners.com/etc-mining-pool)

F2Pool (https://www.f2pool.com/coin/etc)Hiveon (https://hiveon.com/pool/etc)

MiningPoolStats tracks dozens of active pools: https://miningpoolstats.stream/ethereumclassic

Solo mining is still practical for small and mid-size operators. Sites such as https://etc.solopool.org provide estimates for finding blocks with moderate hashrate levels.

Security considerations

Because Ethereum Classic dominates the available Ethash and Etchash hashrate, acquiring sufficient hardware for an attack is difficult. NiceHash removed support for Etchash after the ECIP-1099 upgrade, which limits the ability to rent short-term hashrate.

Performing a majority attack would require acquiring a large number of ASICs or GPUs, which involves high capital cost and lengthy procurement times. The attacker would also suffer opportunity costs because mining produces a steady revenue stream.

Block rewards currently total approximately 2.56 ETC per block, and around 6,000 blocks are mined each day. At an ETC price near $16, this results in roughly $250,000 to $300,000 in daily miner revenue. Any attack must exceed both capital and opportunity costs for participants already earning predictable returns.

Position within the broader ecosystem

Ethereum Classic offers smart contract functionality with a proof-of-work security model. Bitcoin also uses proof-of-work but does not provide a general-purpose execution environment. Ethereum provides a rich smart contract ecosystem but relies on proof-of-stake consensus.

ETC remains EVM-compatible.

Development guides are available at: https://ethereumclassic.org/development/guides

Applications written for Ethereum can generally be deployed on Ethereum Classic without modification. The difference lies in the consensus mechanism and associated security characteristics.

Conclusion

Ethereum Classic demonstrates that a proof-of-work smart contract platform can maintain strong mining participation and broad geographic distribution even after the shift of Ethereum to proof-of-stake. The network’s mining architecture encourages anonymous participation, supports both GPUs and ASICs, and spans many jurisdictions. These characteristics create structural resistance to censorship and central control.

The platform trades higher energy use and a smaller ecosystem for these properties. For applications that require permissionless participation and resilience to regulatory pressure, Ethereum Classic offers a distinctive set of features within the family of EVM-compatible blockchains.

EthereumPoW abandoned

TL:DR: The team who tried to money grab during the merge ran out of money and abandoned the chain.

Ethereum Classic is still the worlds largest Proof of Work EVM network. Decentralized, immutable, and open for business. 

Ethereum Cross Chain Atomic Swaps

In this article, we will create a series of contracts which will allow two people to exchange coins across chains in a trustless atomic manner. An atomic transaction is an indivisible and irreducible series of transactions such that either all occur, or nothing occurs. The contract used is complimentary to BIP-199 so it can be used to transact from ethereum based systems to ethereum based systems or Bitcoin based system(assuming HTLC is allowed).

The difficult problem with cross chain swaps is the off chain coordination required to have the two parties meet and agree on conditions. It is outside the scope of this article, but any communication channel can be used really; email, slack, twitter, reddit, etc….

The background work that makes all of this possible is from BIP-199:

“A Hashed Time-Locked Contract (HTLC) is a script that permits a designated party (the “seller”) to spend funds by disclosing the preimage of a hash. It also permits a second party (the “buyer”) to spend the funds after a timeout is reached, in a refund situation.”

Victor (the “buyer”) and Peggy (the “seller”) exchange public keys and mutually agree upon a timeout threshold.

Peggy provides a hash digest. Both parties can now
 — construct the script and P2SH address for the HTLC.
 — Victor sends funds to the P2SH address or contract.
Either:
 Peggy spends the funds, and in doing so, reveals the preimage to Victor in the transaction; OR Victor recovers the funds after the timeout threshold.

On the Ether chains:

Peggy will be played by account: 0x9552ae966A8cA4E0e2a182a2D9378506eB057580

Victor will be played by account: 0x00D29a21429ad90230aCe2B9a1b25fa35bb288B8

The entire transaction explained:

Peggy will:

  • be locking up funds on etc chain (contract A)
  • that will be sent to Victor
  • when the message that hashes to digest is received

Victor will:

  • be locking up funds on eth chain (contract B)
  • that will be sent to Peggy
  • when the message that hashes to digest is received

Things that need to happen off chain:

  • both parties agree to an exchange rate
  • decide on a reasonable time limit
  • decide on who will lead (generate the preimage)
  • share public addresses

For our test conditions:

  • Peggy is the lead and will generate a sha256 digest off chain
  • Our preimage(“this is a test”) hashes to 2e99758548972a8e8822ad47fa1017ff72f06f3ff6a016851f45c398732bc50c
  • 1 hour timeout
  • 1:50 (1 eth = 50 etc) exchange rate

Everything for the test was deployed to the mainnets of both chains and is there available for review. I have included links where practical. All contracts were deployed with MyEtherWallet using byte code generated from the contract located here. To use this contract as is with out spinning up a node: copy and paste it into remix, fill in the variables for your transaction (hash, time, destination) and copy the byte code to MyEtherWallet to sign and deploy. You will need to create new contracts for your swap .To interact with the contract you can use this abi with the contract address in MyEtherWallet.

Step 1: Contracts are deployed
 Peggy deploys ContractA = 0xa1562aa5ad1e178c56f690c6e776c3c3a2c50193 (etc chain)
 Victor deploys ContractB = 0x7cfc4442dd96d6f85dd41d458a13957ba381e05a (eth chain)

Step 2: Both parties lock funds in their contracts
 Peggy sends .5 etc to 0xa1562aa5ad1e178c56f690c6e776c3c3a2c50193 
 Victor sends .01 eth to 0x7cfc4442dd96d6f85dd41d458a13957ba381e05a

Step 3: claim cross chain funds
 Peggy claims her funds from contract B, reveling the secret 
 Victor read data from contract B , get the key, and claims funds on contract A

That’s it! A little anti-climatic that it only takes 3 steps I guess, but everything on a block chain doesn’t need to be hard. If Peggy never claims her ether, Victor can never claim his. If Peggy does claim her’s she reveals the secret and Victor is free to claim his. The timeout exists so Peggy and Victor can claim their funds if something goes wrong.