2. The cvv of the credit card is also called the security code, which refers to the security code of the credit card when paying by credit card. If you don't know the specific location of this ccv code, you can open the signature on the back of the credit card, and the last three digits in italics are the ccv code. CVV is the number printed in the signature area of Visa/MasterCard card, which is located in the 3 digits after the credit card number. The last three digits we usually see on the back of a credit card are actually CVV 2, not CVV code. CVV 2 and CVC 2 are also the card verification values obtained by the same algorithm, but they are printed on the signature bar when the card is generated. Check CVV/CVC for joint transaction (credit card swiping) and CVV 2/CVC 2 for off-site transaction/manual transaction (credit card swiping is not allowed). VISA card CVV and MC card CVC are 3-digit or 4-digit numbers generated by card number, expiration date and service constraint code, which are generally written on cards.
3. In the dual-track user-defined data area of the magnetic stripe. CVV and CVC are generated in the same way, but they are called in different ways. A verification code (CVN) of a user-defined encryption algorithm is added to the coding rules of bank card number and magnetic stripe data format, and the related bank card is also called CVN bank card. CVV information is stored in the track of magnetic stripe bank card, according to the card number, track master account number, issuer identification code and other information. I wonder if you can understand this explanation.
This cvv 2 can prove that the payer used a credit card when paying, which can prevent the credit card from being cheated. Moreover, the ccv 2 code of a credit card is equivalent to a credit card password, and credit card holders can use this code to swipe their cards. In addition, in some foreign websites, you don't need to enter a password, just need the cardholder to provide the account number and cvv 2 code to complete the transaction. Moreover, the credit cards of many banks in China are the same, and payment can be completed only through anti-counterfeiting codes. Although this ccv 2 code is convenient for payment, it also increases the risk of credit card consumption. Moreover, in recent years, there have been scams that require cardholders to provide cvv 2 codes to help increase the limit. This kind of scam will ask the cardholder to provide the card number, expiration date and security code of the credit card in the name of the bank staff, and will let the cardholder deposit the fee activation card. If the cardholder is in trouble at this time, the so-called customer service staff will ask the cardholder to send him the verification code of the cash withdrawal amount, so that he can get the credit card.