Configure Visa CVM priority

Overview

Visa CVM processing is a negotiation between the digital wallet application and the terminal. It determines which CVM (Cardholder Verification Method) is used to authenticate the end user for a transaction.

Set the CVM priority during SDK initialization by configuring VISA_ONLINEPIN_PRIORITY in your PLIST file. For details, see Configure PLIST file.

Based on this priority, the NFC Wallet SDK selects the best CVM supported by both:

• the digital card profile (CAP)

• the terminal (TTQ)

Inputs used for CVM selection

CAP (card capabilities)

The supported CVMs per AID for a Visa contactless profile are defined by Card Additional Processes (CAP):

Bit mapping	Description
Byte 3 bit 8	1b: Online PIN is supported for domestic transactions.
Byte 3 bit 7	1b: Online PIN is supported for international transactions.
Byte 3 bit 5	1b: Signature is supported.
Byte 3 bit 4	1b: CDCVM is supported.

TTQ (terminal capabilities)

The terminal uses Terminal Transaction Qualifier (TTQ) to indicate what it supports. The bit values are defined as follows:

Bit mapping	Description
Byte 1 bit 3	1b: Online PIN is supported.
Byte 1 bit 2	1b: Signature is supported.
Byte 3 bit 7	1b: CDCVM is supported.
Byte 2 bit 7	1b: CVM is required. (HVT)

“Commonly supported” CVM

A CVM is commonly supported when it is supported by both the card profile (CAP) and the terminal (TTQ).

Online PIN priority

1. Check whether CVM is required (TTQ Byte 2 bit 7 == 1b).

   • If false, proceed as a low-value transaction.

   • If true, continue with step 2.

2. Check if ONLINE_PIN is commonly supported.

   • If true, continue payment processing using Online PIN.

   • If false, continue with step 3.

3. Check if Device CVM is commonly supported.

   • If true, continue payment processing using CDCVM.

   • If false, continue with step 4.

4. Check if SIGNATURE is commonly supported.

   • If true, continue payment processing using signature.

   • If false, no commonly supported CVM exists. The terminal may require POS verification or reject the transaction.

CDCVM priority

1. Check if Device CVM is commonly supported.

   • If true, continue with step 2.

   • If false, continue with step 3.

2. Check if CAP supports CDCVM and if CVM is required (TTQ Byte 2 bit 7 == 1b).

   • If true, proceed to authenticate the high-value transaction.

   • If CAP supports CDCVM but CVM not required (TTQ Byte 2 bit 7 == 0b), proceed with the low-value transaction.

   • If CAP does not support CDCVM, continue with the payment processing using the CARD_LIKE.

3. Check whether CVM is required (TTQ Byte 2 bit 7 == 1b).

   • If false, proceed as a low-value transaction.

   • If true, continue with step 4.

4. Check if ONLINE_PIN is commonly supported.

   • If true, continue payment processing using Online PIN.

   • If false, continue with step 5.

5. Check whether SIGNATURE is commonly supported.

   • If true, continue payment processing using signature.

   • If false, no commonly supported CVM exists. The terminal may require POS verification or reject the transaction.