Command 0X09 - Get Current Tdes Dukpt Ksn - Magtek eDynamo Programmer's Manual

8 - Commands

8.3.4 Command 0x09 - Get Current TDES DUKPT KSN

The host uses this command to get the current Triple Data Encryption Standard (TDES) DUKPT Key
Serial Number (KSN) on demand.
This 80-bit value contains the TDES DUKPT Key Serial Number (KSN) associated with encrypted
values included in the same message. The rightmost 21 bits are the current value of the encryption
counter. The leftmost 59 bits are the device's Initial KSN, which is a combination of the Key Set ID that
identifies the Base Derivation Key (BDK) injected into the device during manufacture, and the device's
serial number (DSN); how those two values are combined into the 59 bit Initial KSN is defined by a
convention the customer defines when architecting the solution, with support from MagTek. For
example, one common scheme is to concatenate a 7 hex digit (28 bit) Key Set ID, a 7 hex digit (28 bit)
Device Serial Number, and 3 padding zero bits. In these cases, the key can be referenced by an 8-digit
MagTek part number ("key ID") consisting of the 7 hex digit Key Set ID plus a trailing "0."
Request Data: None
Table 8-9 - Response Data for Command 0x09 - Get Current TDES DUKPT KSN
Offset Field Name
0 Current Key Serial Number
Result codes:
0x00 = Success
0x02 = Bad Parameter - The Data field in the request is not the correct length. The request command
contains no data, so the Data Length must be 0.
Example Request (Hex)
Cmd Num
09
Example Response (Hex)
Result Code
00
eDynamo| Secure Card Reader Authenticator | Programmer's Manual (COMMANDS)
80-bit TDES DUKPT KSN
00
Data Len
0A FFFF 9876 5432 10E0 0001
Page 71 of 245 (D998200115-17)
Description
Data Len
Data
Data
None