I am working on having our system identify fallback transactions. The Vantiv ISO 8583 Reference Guide V2.0 shows 2 POS Entry Mode values for fallbacks:
- 79 - "Fallback from Chip transactions when keying the prior voice authorization"
- 80 - "Fallback from Chip to magnetic stripe"
What is the difference between the 2 codes? Does a "79" mean that, since there is prior voice authorization, the transaction is not suspicious?