Payment Processing

Payment acceptance, fraud prevention, and forms of payment management. Built on a Zero-Trust Vault Architecture where our servers never touch raw credit card numbers.

Scope

Payment Methods

Credit/Debit Cards: Visa, Mastercard, Amex
UATP: Universal Air Travel Plan
Alternative Payments: PayPal, Apple Pay, Google Pay
Bank Transfers: SEPA, wire transfers
Vouchers: Airline vouchers, gift cards
Loyalty Points: Miles redemption
Buy Now Pay Later: Affirm, Klarna

Fraud Prevention

3D Secure (3DS2)
Address Verification (AVS)
CVV verification
Velocity checks
Machine learning fraud scoring
Manual review queues

Payment Operations

Authorization and capture
Refund processing
Chargeback management
Currency conversion
Tax calculation

OMS Payment Vault

Zero-Trust Architecture

Our servers NEVER touch raw credit card numbers. All sensitive card data is handled by the payment gateway. We only store tokens.

┌─────────────────────────────────────────────────────────────────┐
│                   Zero-Trust Payment Flow                       │
│                                                                 │
│  ┌──────────┐                                                   │
│  │ Customer │                                                   │
│  └────┬─────┘                                                   │
│       │                                                         │
│       │ Credit Card Data                                        │
│       ▼                                                         │
│  ┌──────────────────┐                                           │
│  │ Payment Gateway  │◄── Hosted payment page                    │
│  │    (API)         │    PCI-compliant capture                  │
│  │                  │                                           │
│  │  ┌────────────┐  │                                           │
│  │  │ Processing │  │                                           │
│  │  │  Platform  │  │                                           │
│  │  └────────────┘  │                                           │
│  └────────┬─────────┘                                           │
│           │                                                     │
│           │ Payment Token (Safe)                                │
│           ▼                                                     │
│  ┌──────────────────┐         ┌────────────────┐               │
│  │    OMS Vault     │────────►│  Domestic Tax  │               │
│  │                  │         │    Engine      │               │
│  │  ┌────────────┐  │         │                │               │
│  │  │ Order ID   │  │         │ Applies GST/VAT│               │
│  │  │ Token Ref  │  │         │ based on O&D   │               │
│  │  │ Last Four  │  │         └────────────────┘               │
│  │  │ Amount     │  │                                           │
│  │  └────────────┘  │                                           │
│  └──────────────────┘                                           │
│                                                                 │
│  What we store:              What we DON'T store:               │
│  ✓ Payment token             ✗ Full card number                 │
│  ✓ Last 4 digits             ✗ CVV/CVC                          │
│  ✓ Expiry (month/year)       ✗ Full PAN                         │
│  ✓ Order ID                  ✗ Track data                       │
│                                                                 │
└─────────────────────────────────────────────────────────────────┘

Payment Vault Data Model

model PaymentVault {
  id            String    @id @default(uuid()) @db.Uuid
  orderId       String    @unique @db.Uuid
  order         Order     @relation(fields: [orderId], references: [id])

  // Token from payment gateway - NEVER raw card data
  tokenRef      String    // Gateway-specific token
  gatewayId     String    // Which gateway issued the token

  // Display only - for customer reference
  lastFour      String?   @db.VarChar(4)
  expiryMonth   Int?
  expiryYear    Int?
  cardBrand     String?   // Visa, Mastercard, etc.

  // Transaction details
  amount        Decimal   @db.Decimal(10, 2)
  currency      String    @db.VarChar(3)
  status        PaymentStatus @default(PENDING)

  // Authorization
  authCode      String?
  authTimestamp DateTime?
  authExpiry    DateTime?

  // Capture
  capturedAt    DateTime?
  capturedAmount Decimal? @db.Decimal(10, 2)

  // Audit
  createdAt     DateTime  @default(now())
  updatedAt     DateTime  @updatedAt

  // NO fields for: cardNumber, cvv, fullPan, trackData

  @@index([orderId])
  @@index([status])
}

enum PaymentStatus {
  PENDING
  AUTHORIZED
  CAPTURED
  REFUNDED
  FAILED
  CANCELLED
}

Benefits of Zero-Trust

Benefit	Description
PCI Scope	SAQ A (minimal) - card data never enters our systems
Security	Zero card data = zero card data breaches
Compliance	Simplified audit, reduced liability
Operations	No secure card data handling processes needed

Research Topics

Architecture Considerations

Payment Flow

Customer Checkout
       ↓
┌──────────────────┐
│ Payment Gateway  │ ◄── PCI-compliant token capture
└────────┬─────────┘
         │
    ┌────┴────┐
    │         │
┌───▼───┐ ┌───▼───┐
│ 3DS   │ │ Fraud │
│ Auth  │ │ Check │
└───┬───┘ └───┬───┘
    │         │
    └────┬────┘
         │
┌────────▼────────┐
│   Authorize     │
└────────┬────────┘
         │
    (Booking confirmed)
         │
┌────────▼────────┐
│    Capture      │ ◄── At ticketing or check-in
└─────────────────┘

Payment Data Model

Payment
├── PaymentID
├── OrderReference
├── Method
│   ├── Type (Card, UATP, Wallet, etc.)
│   ├── Token (PCI tokenized)
│   └── Details (masked)
├── Amount
│   ├── Currency
│   ├── Value
│   └── ExchangeRate
├── Authorization
│   ├── Code
│   ├── Timestamp
│   └── ExpiryDate
├── Status (Pending, Authorized, Captured, Refunded)
└── FraudScore

Authorization Strategies

Strategy	Use Case
Auth + Capture	Immediate ticketing
Auth only	Deferred ticketing
Pre-auth + Incremental	Ancillary add-ons
Zero-auth	Card validation

Integration Points

System	Direction	Data
Booking Engine	Inbound	Payment requests
Payment Gateway	Bidirectional	Auth/capture
Fraud System	Bidirectional	Risk scores
Ticketing	Outbound	Payment confirmation
Refunds	Bidirectional	Refund processing
Finance	Outbound	Settlement data

Gateway Selection

Key Providers

Provider	Strengths
Adyen	Global, airline experience
Worldpay	High volume, fraud tools
Cybersource	Enterprise, analytics
Stripe	Developer experience
Checkout.com	Modern API, competitive rates

Selection Criteria

Geographic coverage
Payment method support
Fraud tools
Pricing model
PCI scope reduction
Airline industry experience

PCI-DSS Compliance

Scope Reduction

Use hosted payment pages
Tokenization for storage
Point-to-point encryption (P2PE)
No card data in logs

Compliance Levels

Level	Transactions/Year	Requirement
1	>6M	Annual audit
2	1-6M	SAQ + quarterly scan
3	20K-1M	SAQ
4	<20K	SAQ

Fraud Management

Risk Signals

IP geolocation
Device fingerprint
Booking velocity
One-way/cash tickets
High-risk routes
Last-minute bookings

Response Actions

Risk Level	Action
Low	Auto-approve
Medium	3DS challenge
High	Manual review
Critical	Auto-decline