System Architecture

The PAYDAO payment system adopts a decentralized architecture. Its core consists of the payment protocol, payment terminals, payment cards, and supporting application software.

┌──────────────────────┐
│      User Side       │
│ (Payment Card + APP) │
└──────────┬───────────┘
           │
           │ NFC Payment
           ↓
┌──────────────────────┐   Blockchain Transaction   ┌──────────────────────┐
│    Merchant Side     │ <────────────────────────> │   Payment Protocol   │
│  (Payment Terminal)  │                            │  (Fund Management)   │
└──────────┬───────────┘                            └──────────────────────┘
           │
           │ Withdrawal
           ↓
┌──────────────────────┐
│  External Wallet     │
│     (Merchant)       │
└──────────────────────┘