2MPC Flow

Deposit Flow

How a user moves an external asset onto SBChain using a 2MPC vault:

User initiates deposit in SwapBlok UI
        ↓
UI requests Key Share A participation from user's device
        ↓
ika.xyz dWallet network provides Key Share B
        ↓
2MPC protocol runs — full signing key never assembled
        ↓
Co-signed transaction locks funds in the 2MPC vault address
        ↓
Lock event emitted on source chain (Ethereum / Solana / Bitcoin / Tron)
        ↓
Relayer detects event, constructs Merkle proof
        ↓
SBChain consensus verifies proof independently
        ↓
Equivalent IOU or wrapped asset minted to user's SBChain account

Withdrawal Flow

How a user moves an asset back to an external chain:

User initiates withdrawal in SwapBlok UI
        ↓
SBChain burns / locks the on-chain asset
        ↓
Withdrawal request recorded on SBChain
        ↓
UI requests Key Share A from user's device
        ↓
ika.xyz dWallet network provides Key Share B
        ↓
2MPC protocol produces co-signed release transaction
        ↓
Release transaction broadcast to destination chain
        ↓
Funds arrive at user's external address

Why Neither Party Can Act Alone

• SwapBlok has no key share — it cannot initiate or block a transaction independently
• ika.xyz has Key Share B only — useless without the user's Key Share A
• The user has Key Share A only — useless without ika.xyz providing Key Share B
• Only the user, by actively participating in the MPC protocol, can authorise movement of their funds

2MPC Primitive Summary