The CVV2 code of China Merchants Bank is called CardVerificationValue2. For Mastercard, it is called CardValidationCode (CVC). This security code is generated from the credit card information, including the card number, expiration date and service restriction code. It is usually visible on the card's magnetic stripe in Track 2 of the user-defined data area and is presented as a 3-digit or 4-digit number.

CVV2 and CVC are essentially the same, but have different names. On Visa and MasterCard cards, you will find CVV2 in the last three digits of the signature area, rather than the commonly known CVV. These numbers are generated through complex algorithms, and only the holder and the issuing bank know their exact values.

It is worth noting that CVV2 is an important part of credit card security. It is stored in the magnetic strip and encrypted through the bank's custom encryption algorithm, such as CVKA technology, so that even illegal activities that obtain part of the bank card information cannot be easily copied and used. The encryption algorithms of each bank are different, allowing counterfeit cards to be identified when decrypted by the issuing bank, thus enhancing the security of the card.

In general, China Merchants Bank CVV2 code is a key element to ensure the security of your credit card transactions, so it must be kept properly.

Reference material: Baidu Encyclopedia-CVV code