Secure Payment Gatewate. What’s SPG?
In order to guarantee the security in the purchase, it is used a service that authorizes payments by a safe connection SSL (Secure Socket Layer), encoding the communications that contain sensitive information such as the numbers of credit cards or debit ones. Once the buyer introduces sensitive information, the whole transaction till the payment is completed is transmitted on the protocol HTTPS (http secure). You can find a lot of information about it on pages specialized in the security of web environments.