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CVV is calculated:

To calculate[CVV Generate] verb generates a 3-digit CVV, that is based on the CVV algorithm requires a Primary Account Number (PAN)information that the PAN_data, a 4-digit Expiration Datethe expiration_date, a 3and the service_code parameters provide. This verb uses the Key-digit Service Code,A and a pair of DESthe Key-B keys (CVKs)to cryptographically process this information. 

Source: http://www.darkcoding.net/credit-card/cvv-numbers/https://www.ibm.com/support/knowledgecenter/en/linuxonibm/com.ibm.linux.z.wskc.doc/wskc_r_csg.html

This calculation can only be done by the card issuer due to the use of secret CVK,a pair of Cryptographic keys which is known only byto the card issuer.

CVV is calculated:

To calculate a 3-digit CVV, the CVV algorithm requires a Primary Account Number (PAN), a 4-digit Expiration Date, a 3-digit Service Code, and a pair of DES keys (CVKs).

Source: http://www.darkcoding.net/credit-card/cvv-numbers/

This calculation can only be done by the card issuer due to the use of secret CVK, which is known only by the card issuer.

CVV is calculated:

[CVV Generate] verb generates a CVV that is based on the information that the PAN_data, the expiration_date, and the service_code parameters provide. This verb uses the Key-A and the Key-B keys to cryptographically process this information. 

Source: https://www.ibm.com/support/knowledgecenter/en/linuxonibm/com.ibm.linux.z.wskc.doc/wskc_r_csg.html

This calculation can only be done by the card issuer due to the use of a pair of Cryptographic keys which is known only to the card issuer.

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source | link

CVV is calculated:

To calculate a 3-digit CVV, the CVV algorithm requires a Primary Account Number (PAN), a 4-digit Expiration Date, a 3-digit Service Code, and a pair of DES keys (CVKs).

Source: http://www.darkcoding.net/credit-card/cvv-numbers/

This calculation can only be done by the card issuer due to the use of secret CVK, which is known only by the card issuer.