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The bank card password depends on the bank card password verification technology, and commercial banks add the card encryption verification code (CVN) of the self-defined encryption algorithm to the bank card number coding rules and magnetic stripe data formats they use. This password verification technology is called CVV for short.
First, CVV password verification
This technology is compatible with the basic technical standards of bank cards, such as ISO78 13 identification card standard (financial transaction card) and GB/T 15 120 (recording technology). CVV information is stored in the second track of the magnetic stripe bank card. According to the information such as bank card number, Track 2 main account number (PAN), card issuer identification code, card issuer identification code, card issuing outlet identification code, start mark, end mark, separator (SF), etc., it is calculated by a special encryption algorithm defined by each bank. After each calculation is encrypted by CVKA technology, the bank card encryption verification code (CVN) is obtained. Different banks have different encryption algorithms and security technologies, so criminals can use the obtained bank card information to make fake cards, which can be recognized by the issuing bank when decrypting, but cannot be used.
Second, SSL security protocol.
SSL security protocol, also known as "Secure Sockets Layer" protocol, was designed and developed by Netscape Communications Company in 1996, which is mainly used to improve the data security coefficient between applications. SSL security protocol mainly provides three services: one is the legal authentication of users and servers, the other is the encryption of data to hide the transmitted data, and the third is the protection of data integrity. SSL protocol involves all TCP/IP applications, and it is a protocol to ensure the security between any client and server with Secure Sockets Layer installed. However, with the rapid increase of participation in e-commerce, the problem of supplier authentication is becoming more and more prominent, so SSL security protocol is gradually replaced by SET protocol.
Three. Setting protocol
SET protocol, also known as secure electronic transaction specification, is the rule of credit card-based electronic transaction security measures introduced by MasterCard and Visa in 1996. It is a secure electronic payment protocol and can be widely used in the Internet. RSA and DES algorithms are used in the authentication process, forming a standard for safe use of bank cards in online shopping. But the authentication process of SET protocol is very complicated. Each transaction needs to verify the electronic certificate 9 times, verify the digital signature 6 times, transmit the certificate 7 times, sign 5 times, encrypt symmetrically 4 times and encrypt asymmetrically 4 times. It takes a long time to complete a transaction containing the SET protocol, so this protocol has not been popularized.