When using Sophon, you’ll notice a specific period of time before your transaction is finalized, meaning that any state change generated by the transaction has been made available and proven on Ethereum (and thus considered final). This delay is not arbitrary - it is critical to Sophon’s security and core operations. For this reason withdrawals from Sophon to Ethereum are not immediately available, requiring time before they can be claimed. This time is dependent on two primary factors:

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Proof Generation and Validation

TLDRProof generation balances security, cost, and speed. The time taken to generate proofs ensures L2 transactions are secure, valid and timely. This is why withdrawals from Sophon Mainnet can only be completed once a proof becomes available on Ethereum.
Proof generation can take a long time for several reasons:
  • Proof Complexity: L2 blockchains create complex cryptographic proofs (which take time and resources to complete) to validate transactions without revealing all the details.
  • Transaction Batching: L2 chains group transactions into one proof to save on costs. This batching means waiting for enough transactions before a proof can be generated.
  • Processing Power: L2 blockchains rely on sequencers or validators to handle transactions and proofs. If these systems become overloaded or slowed up, proof generation can take longer.

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Transaction Execution Delay

Sophon is an L2 blockchain built using the ZKsync Stack. This means that transactions first have to be processed on Sophon Mainnet and then on Ethereum. To ensure nothing can go wrong, the following processes are necessary:
  • ZKsync’s team constantly monitors blocks for suspicious activity, such as large withdrawals or rapid outflows.
  • If a hacker finds a critical bug, it cannot be exploited as security measures are in place to detect any anomalies, allowing for the necessary action to be taken.
This is why ZK Stack chains have a batch execution delay in place. At present, this delay lasts 3 hours. Regardless, every L2 block on Sophon Mainnet committed to Ethereum (L1) must be finalized, allowing enough time for ZK proofs to be generated and validated on L1 before the chain state is updated and considered final. It is expected that proof generation and validation happens within the 3 hours delay, but for multiple reasons it might take more time. So if you withdraw doesn’t become available for claiming after 3 hours, don’t worry, it just means proofs are still begin generated.
For more info on withdrawal delays, see ZKsync’s docs.