C-TAP is the abbreviation of Common Terminal Acquirer Protocol. The C-TAP specifications describe:
The exchange of information with payment cards of various technology and how these cards are recognized
The detailed flow for various types of transaction processing
The association of a recognized card with an acquirer that will authorize and settle the transaction
The data exchange with this processor
The message and information processing requirement at the acquirers’ host system
In more detail, the C-TAP specifications indicate:
Storage and management of card recognition criteria and multiple sets of instructions delivered by individual acquirers having a relationship with the merchant
The sequence of interactions with EMV smart cards on top of the EMV Level 1 and Level 2 specifications, as well as the reading of ISO tracks on magstripe cards
The support of the various CVM (Cardholder Verification Method) as instructed by the issuer of the card in combination with the directions delivered by the acquirer: clear text or encrypted PIN verified by the smart card, encryption and on-line verification of a PIN, signature or no CVM
The support of various modes of operation: on-line and backup mode
A range of solutions to guarantee message integrity and data protection
