⛓️ Blockchain & Web3 · Sequence
Crypto Withdrawal Sequence
How an exchange processes a crypto withdrawal safely: balance hold, 2FA, risk and address screening, signing, broadcast and confirmations.
Drawing diagram…
What this diagram shows
- Funds are held first so they can't be spent twice
- Addresses are screened against sanctions lists
- The withdrawal completes after enough block confirmations
Prompt used
Crypto withdrawal: the user requests a withdrawal of 0.5 ETH to an address and confirms with 2FA. The wallet service asks the ledger to hold the amount, asks compliance to screen the address, signs the transaction with the hot wallet signer (HSM), broadcasts it to an Ethereum node and waits for 12 confirmations, then marks the withdrawal complete and releases the hold as spent.
Mermaid code
sequenceDiagram
actor U as User
participant W as Wallet Service
participant L as Ledger
participant C as Compliance
participant S as HSM Signer
participant N as Ethereum Node
U->>W: Withdraw 0.5 ETH to address, with 2FA code
W->>L: Hold 0.5 ETH
L-->>W: Held
W->>C: Screen address and amount
C-->>W: Cleared
W->>S: Sign transaction
S-->>W: Signed transaction
W->>N: Broadcast
N-->>W: Transaction hash
loop Until 12 confirmations
W->>N: Check confirmations
end
W->>L: Mark hold as spent
W-->>U: Withdrawal completeRelated templates
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