SCA Functional Specification

Reasons for SAF

SCA can be configured to perform SAF for various reasons

• Network Issues

  • LAN (Local Area Network)

    • Loose or damaged LAN cable
    • WiFi or LAN configuration issue (DNS, etc.)

  • WAN (Wide Area Network)

    • ISP (Internet Service Provider) issue
    • General internet issue

  • Gateway

    • Gateway down

  • Host

    • Host down

• Other reasons for SAF

  • A command from POS to trigger a SAF mode transaction
  • Gateway response (configured) to perform SAF
  • Certificate issues (cannot authenticate to gateway/host)
  • Host reachable but error responses indicate host internal/backend issues

Supported Transactions

Supported Card Types

Following are the card types supported

• Credit
• Gift
• Private Label

SAF Flow

Rules

• When the SAF configuration parameter is enabled and there is loss of connectivity to the server, the payment acceptance device can locally approve transactions below a set floor limit.
• SAF approvals are processed untill certain duration or till MAX limit is reached.
• The stored transactions are written to a queue within the payment device
• Transactions from the SAF queue are sent to the gateway periodically when the application can connect
• When the transaction amount is greater than or equal to the floor limit, then an approval code would be required by the bank to proceed with the transaction. Once approval code is acquired, the POS would send another CAPTURE command including the approval code acquired. This transaction gets added to the SAF queue

Configuration Parameters

Following are the configuration parameters which affect the operation

• ALLOWGIFTACTIVATETOSAF
• ALLOWREFUNDTOSAF
• ALLOWVOIDTOSAF

Messages Commands

Refer to the below Protocol sections for the command fields description and examples.

• SAF QUERY
• SAF EDIT
• SAF REMOVE