Verified by Visa

VbV is a service that has been implemented in other parts of the world and was implemented by Visa Canada in April 2003. VbV provides authentication of cardholder identity for real time Internet based credit card transactions. Through a series of web based messages and exchanges at the point of purchase, the cardholder's the card issuer confirms identity and that confirmation or denial is communicated to the merchant. The confirmation data is then appended to the traditional authorization message and the chargeback liability traditionally attributed to these unsigned card-not-present transactions is no longer the responsibility of the merchant.

Additional information is available on the Visa website. It is suggested that you read Visa's Best Practices document.