4D Payments SDK 2016 .NET Edition

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KSN Property

Clear-text Key Sequence Number retrieved from a PIN pad.


public string KSN { get; set; }
Public Property KSN As String

Default Value



A 19 or 20-byte Key Sequence Number (KSN) and associated EncryptedPIN are required for all debit Sale and Credit transactions. These values must be retrieved from a certified DUKPT DES pin pad device. A 20-byte Key Sequence Number consists of a 1-byte pad character ('F'), a 9-byte Base Derivation Key Id (BDK ID), a 5-byte device Id, and a 5-byte transaction counter. If this property is set with a Key Sequence Number less than 20 bytes in length, the component will pad it on the left with 'F' characters.

This value is required for all transactions except Full Reversals.

Debit Sale Example

debit.TPPID = "AAA000";
debit.MerchantTerminalNumber = "00000001";
debit.MerchantId = "1234";
debit.GroupId = "20001";
debit.DatawireId = "00011122233344455566";
debit.ApplicationId = "RAPIDCONNECTVXN";
debit.URL = "https://stg.dw.us.fdcnet.biz/rc";

debit.STAN = "112";
debit.TransactionNumber = "1234";
debit.ReferenceNumber = "1212";
debit.OrderNumber = "123";

debit.Card.MagneticStripe = "4003010001234572=17041011234567440";
debit.EncryptedPIN = "7BD8948B328B21E5";
debit.KSN = "876543210F008400029";

debit.TransactionAmount = "1200";

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4D Payments SDK 2016 .NET Edition - Version 16.0 [Build 8017]