Gateway (Secure payment gateway)
A gateway or a secure payment gateway is an independent service which acts as an intermediary between the merchantís shopping cart and the different bank networks involved in the transaction, (the purchaserís bank card bank and the sellerís merchant account bank)
The gateway verifies the validity and encrypts the details of each transaction, ensures of the correct destinations for the data, and decodes the responses sent back to the shopping cart.
This is an integrated, invisible process; the purchaser only interacts with the shopping cart and the payment confirmation pages. The information is sent from the shopping cart to the gateway via a secure connection.
Gateway and shopping cart are two different things; the two communicate with each other and each one has a distinct role to play. The shopping cart sends the information relating to the order (bank card details and amount of the order) to the gateway.