For live transactions, you receive a merchant ID for Google Pay from us. This is passed to the Google Pay button of your checkout solution.
The payment process itself works similar to other payment methods. When one operates the Google Pay button, the payment instrument is chosen and the necessary security checks are performed. The Google API returns a security token, that must be handed over to authorise the payment against the secuconnect API.
The secuconnect API methods to authorise and capture the payment are the same like for credit card payment, except there are no callback URLs for there is no second interactive 3-D Secure check, and there is a special Payment Container for Google Pay.