View source for How to Understand DUKPT

== Description ==
Derived Unique Key per Transaction - a key management method which uses a unique key for 
each transaction, and prevents the disclosure of any past key used by the transaction-originating 
TRSM. The unique Transaction Keys are derived from a base derivation key using only non-secret 
data transmitted as part of each transaction.

DUKPT allows the processing of the encryption to be moved away from the devices that hold the shared secret. The encryption is done with a derived key, which is not re-used after the transaction. DUKPT is used to encrypt electronic commerce transactions. While it can be used to protect information between two companies or banks, it is typically used to encrypt PIN information acquired by Point-Of-Sale (POS) devices.
DUKPT is not itself an encryption standard; rather it is a key management technique. The features of the DUKPT scheme are:
* Enable both originating and receiving parties to be in agreement as to the key being used for a given transaction,
* Each transaction will have a distinct key from all other transactions, except by coincidence,
* If a present derived key is compromised, past and future keys (and thus the transactional data encrypted under them) remain uncompromised,
* Each device generates a different key sequence,
* Originators and receivers of encrypted messages do not have to perform an interactive key-agreement protocol beforehand.

Our internal PINPad support 3 DUKPT keys. They are PIN key, MAC key and data key. Different key only can be used to encrypt different data.

== Inject ==
Please refer to [[How to inject test key(master key or DUKPT key) remotly]] or use [[TMK Deliver System Usage（For KeyLoader POS/Master POS）]]

== Usage ==
Please refer to our SDK, the description of the pinpad. Please download the [http://ftp.wizarpos.com/advanceSDK/DukptDemo.zip dukpt demo app].