A Crypto-to-Fiat bridge (On-ramp/Off-ramp) sits between two incompatible ledgers: The Blockchain (Ethereum, Solana) and the Banking System (SWIFT/ACH). Reconciliation here is determining that TxHash_0x123 (sending USDC) corresponds to Bank_Wire_Ref_ABC (receiving USD). The speed mismatch (Seconds vs Days) creates massive volatility risk.
The Three-Legged Recon
On-Chain Leg: The user sends crypto to the Bridge Wallet. The "Watcher Service" detects Confirms > 12.
Internal Leg: The system locks a rate and records a Pending_Payout.
Fiat Leg: The system instructs the bank to wire USD.
The Challenge: The bank wire might fail 2 days later. The crypto is already gone. The ledger must hold the crypto in a "quarantine" state until the Fiat leg reaches a terminal state, or accept the credit risk.
Mint and Burn Management
For Stablecoin issuers:
Minting: Fiat deposit received -> Mint Token. Bank_Asset increases, Token_Liability increases.
Burning: Token redeemed -> Burn Token -> Send Fiat.
Proof of Reserves: The automated reconciliation job must prove Total_Fiat_In_Bank >= Total_Tokens_On_Chain. This query is published often via Oracle for transparency.
