ELM Encryption Advance DDK Message (Tran Type 36-08)

Simplify supports an ELM Encryption Advance DDK message from the POS process.

The POS system can send Simplify an ELM Encryption Advance DDK request when the POS system wants to cause Simplify to have ELM advance to the next available DDK.

For a guide on when to use this command, please refer to the Verifone document:

Derived Key Merchant Implementation Overview

Care should be taken to ensure that this message is sent only once if responded to. Verifone states that there are 90 Derivation Keys configured in the PIN Pad. If the keys are changed every year, the keys should then last 90 years.

Before sending the ELM advance DDK message, please ensure that the Simplify PIN Pad has already registered with the Verifone VSP server. If the Simplify PIN Pad is able to process financial credit requests using the locator values (fields 109, 8002, 8006), then Advance DDK can be sent as long as the locator values do not change.

If an Advance DDK is sent with different values from those sent in the authorization requests, then the Simplify will register the PIN Pad to the VSP server without advancing to the next DDK.

The response for the Advance DDK will look like an approval message because Simplify will just echo a message sent by FuseBox for the Informational message. Whatever the response, please do not retry the advance DDK message as the PIN Pad has a limited number of DDK’s.

Sample Message


An example of an ELM Encryption Advance DDK Request message (from the POS to Simplify) is:

API Field #, ValueDescription
0001,36Transaction Type 36. Non-Financial message.
0007,1025Transaction ID/Reference Number
0011,xxx..User Data. See Simplify-Controlled Field Definitions for the use of this field.
0013,092818Transaction Date (current date). MMDDYY
0014,143034Transaction Time (current time). HHMMSS
0109,TERM1Terminal ID (provided by Elavon)
0110,205Operator ID.
8002,RETL01Location Name (provided by Elavon)
8006,TSTLARChain Code (provided by Elavon)


An example of an ELM Encryption Advance DDK Response message (from Simplify to the POS) is:

API Field #, ValueDescription
0001,2Transaction Type 36. Non-Financial message.
0002,3.00Transaction Amount
0003,***********0017Masked Account data
0004,0251Expiration Date MMYY
0007,000246Transaction ID/Reference Number.
0011,xxx..User Data. See Simplify-Controlled Field Definitions for the use of this field.
0013,092818Transaction Date (current date). MMDDYY
0014,143042Transaction Time (current time). HHMMSS
0017,0.00Cash back amount
0052,5Transponder / Proximity Indicator (0 = contact; 2 = contactless; 5 = swiped)
0054,90POS Entry Mode
0109,TERM1Terminal ID (provided by Elavon)
0110,555555Operator ID.
0115,010Transaction Qualifier (010 = credit; 030 = debit)
0126,2Track Indicator (may need to appear on receipt)
0140,USDFusebox – Merchant Currency
1003,0285Gateway Response Code
1004,VF-ADVANCE DDK SUCCESSHost Response Message
1008,***********0017Masked Account Number (for printing on receipt)
1009,909Host Response Code
1010,VERIFONE COMPLETEGateway Response Message
5002,282555552Device Serial Number
5004,V1Encryption Provider ID
7007,1114030712236440Transaction Link Identifier (a unique identifier to link transactions)
8002, RETL01Location Name (provided by Elavon)
8006, TSTLARChain Code (provided by Elavon)