Since some behaviour of nexoFAST are not adequate for some user, we have put in place some flags to support certain conditions to deviate from the pure nexoFAST specification.
By default, if not present, the value must be set to 0x00000000, in order to be compliant to nexoFAST.
New data elements
Arkos Custom NexoFAST Processing
Template : 0xFFFF57
Tag : 0xDF05
Length (in bytes) : 4
Format : b
Value : Specifies the possible custom behaviours. (Based on ISO20022 caaa 2016-2017)
Source : Terminal Configuration (Terminal, E1)
Byte | b8 | b7 | b6 | b5 | b4 | b3 | b2 | b1 | Meaning |
---|---|---|---|---|---|---|---|---|---|
1 | 1 |
|
|
|
|
|
|
| Allow to insert another EMV Card in fallback |
| 1 |
|
|
|
|
|
| Fallback not allowed on valid ATR card | |
|
| 1 |
|
|
|
|
| Display message “Card Not Supported” on unknown card | |
|
|
| 1 |
|
|
|
| Match IIN before removing subordinated AID (use for US Debit Filtering) | |
|
|
|
| 1 |
|
|
| Display message “Use Chip Reader” after an invalid swipe as occured (such as a card with chip on it) | |
|
|
|
|
| 1 |
|
| RFU | |
|
|
|
|
|
| 1 |
| RFU | |
|
|
|
|
|
|
| 1 | RFU | |
2 | 1 |
|
|
|
|
|
|
| RFU |
| 1 |
|
|
|
|
|
| RFU | |
|
| 1 |
|
|
|
|
| RFU | |
|
|
| 1 |
|
|
|
| RFU | |
|
|
|
| 1 |
|
|
| RFU | |
|
|
|
|
| 1 |
|
| RFU | |
|
|
|
|
|
| 1 |
| RFU | |
|
|
|
|
|
|
| 1 | RFU | |
3 | 1 |
|
|
|
|
|
|
| RFU |
| 1 |
|
|
|
|
|
| RFU | |
|
| 1 |
|
|
|
|
| RFU | |
|
|
| 1 |
|
|
|
| RFU | |
|
|
|
| 1 |
|
|
| RFU | |
|
|
|
|
| 1 |
|
| RFU | |
|
|
|
|
|
| 1 |
| RFU | |
|
|
|
|
|
|
| 1 | RFU | |
4 |
|
|
|
|
|
|
|
| RFU |
Allow to insert another EMV Card in fallback
The nexo-FAST behaviour in case of fallback is to not allow card entry in case of fallback. We create a flag to bypass this behaviour. We change the outlined condition to the following one :
Fallback Flag = TRUE AND ACNP[1,8] <> 1b ?
Fallback not allowed on valid ATR card
On unknown EMV cards, fallback is allowed by default.
Some users which to not support this feature, so a flag is created to abort instead of going in fallback.
We change the outlined condition to add the following condition :
- AND ACNP[1,7] <> 1b (Fallback not allowed on valid ATR card)
Display message “Card Not Supported” on unknown card
On unknown cards, by default, no special message is displayed. This can leave the cardholder confused. Therefore, a flag is created to display a new Cardholder message to inform the user that the card is not supported.
This message is conditional that the card is not blocked.
We change the outlined section to add the following new process :
if Nok Reason <> Card Blocked AND
ACNP[1,6] = 1b (Display Card Not Supported) AND
Cardholder Confirmed Once = FALSE
Match IIN before removing subordinated AID (use for US Debit Filtering)
On US Market, when supporting Debit, Debit Pairs must be identified before removing AID in the process “7.4.2.2.5 Process on Candidate List”.
To support that, if the flag is raised, a check is added to match IIN for both Candidate. Only if both IIN are present and matching will the subordinated AID be removed.