What does External Authenticate mean?
Some tests require or dont require the terminal to process an External Authenticate command.
The EXTERNAL AUTHENTICATE command asks the application in the ICC to verify a cryptogram which is present in EMV TAG 91 in the response.
External authentication is performed by the terminal if:
- AIP (Application Interchange Profile) indicates issuer authentication is supported.
- Tag 91 is present in 0110/0210 message in DE55 field.
So if above conditions are met, irrespective of whether the response is an approval or decline, the external authentication should be performed.