I am working on EMV technology and looking for the communication ( Request/Response) between terminal and issuer for authorization / online pin checking.
I know Offline data authentication check on terminal only and then terminal send data to issuer. I wonder what data need to send for authorization process.
I know little bit about DE elements ( like DE-55 element - contain data like Amount,Authorised(Numeric) ,Amount,Other(Numeric),ApplicationCryptogram(AC)).
Could anybody give me a link/documnent where I can see what and how communication in what format happening between Terminal and issuer for authorization (cryptogram validation) , Online PIN checking , CVV validation and all.
sorry for my bad english.
Terminal communicates only with the acquirer. The communication between terminal and acquirer is determined by acquirer host system like Compass+, OpenWay, other and specific implementation you can ask your host provider (easier to ask the Bank for which the terminal will be the point of sale ). In common this all protocols are based on ISO8583, so you could read there. Also some information you can find at EMV Book 4, 12 Acquirer Interface.
EMV Book 4:
An authorisation message shall be used when transactions are batch data captured. A financial transaction message shall be used when online data capture is performed by the acquirer. An offline advice shall be conveyed within batch data capture when supported. An online advice or a reversal message shall be transmitted real-time, similarly to an authorisation or financial transaction message.