A Point-of-Sale (POS) system is the starting point of nearly every electronic payment. Although it looks simple to the end user — tap a card, enter a PIN, get a receipt — a POS is actually a secure, certifiable embedded system that sits at the front line of the payment ecosystem.

In functional terms, a POS system allows a merchant to accept payments.
In architectural terms, it is a security-critical endpoint in a much larger network that includes acquirers, card schemes, issuers, payment gateways, and certification bodies.

Why POS Systems Matter

A POS device or application must:

• Capture card data securely
• Apply EMV logic (terminal risk checks, data authentication, CVM processing)
• Protect sensitive key material
• Generate secure cryptograms
• Communicate with the acquirer using ISO 8583 or host APIs
• Maintain auditability, integrity, and compliance

This requires a blend of:

• Embedded development
• Cryptography
• Secure key management
• Payment certification processes
• Real-time, reliable networking

Types of POS Systems

• Traditional POS terminals
• SmartPOS (Android-based)
• SoftPOS (Tap-to-Phone / COTS devices)
• mPOS / PIN-on-Glass
• Virtual POS for in-app payments

Each introduces different security models, key management needs, and certification requirements.

POS as Part of a Larger Architecture

A POS system is not standalone. It participates in:

• EMV transaction flows
• Acquirer host communication
• Risk management
• Scheme compliance
• Merchant reporting
• Device lifecycle management (TMS/MDM)

Understanding this broader context is crucial for building secure, certifiable systems — and is the foundation of the content shared here on Corebaseit.