Card Input
Payload
HMAC Signature
API Configuration
Protocol 101.x vs 201.x
| Aspect | 101.x | 201.x |
|---|---|---|
| Transport | HTTPS | Mutual TLS |
| Encryption | AES-128/256 | AES-256 + Rotation |
| Authentication | API Key + HMAC | Cert + HMAC |
| Risk Level | Medium | Low |
| Use Case | Retail | Bank / Switch |