Additional data to or from host
Overview
Additional tags are used to send data in the authorization request that are returned in the settlement logs to the Merchant or are used by NEXI to activate specific services, like tokenization.
The formatting of these tags is different per Bank:
Intesa San Paolo
- Data can be inserted in the tag with index 5.
- The maximum length of the tag is 100 bytes.
Other Banks
- Data can be inserted in a maximum of 4 tags with index from 1 to 5.
- The maximum length of concatenated data is 100 bytes (not considering control characters and separators).
- The maximum length of tags from 1 to 4 is 30 bytes
- The maximum length of tag 5 is 100 bytes
The ADDITIONAL DATA FOR GT application message is only expected from the POS terminal when, in the single procedure activation commands, the relevant flag is found (“Presence of message with additional data for the GT”).
There are two fields in this message that inform the terminal whether it should send the “additional data from GT message” after the procedure result message. The message with additional data is the only message that contains fields with variable length, indicated with the letter V in the LENGTH column in the table below.
Additional data for GT delivery message (from ECR)
| Pos | Length | Type | Content |
|---|---|---|---|
| 1 | 8 | N | Terminal ID (00000000-99999999) |
| 9 | 1 | A | Reserved – fixed to ‘0’ (0x30) |
| 10 | 1 | A | Message code: ‘U’ (0x55) |
| 11 | 6 | N | Payment Type:
|
| 17 | 2 | N | ISO field number. Indicates the ISO-8583 field where data from GT that must be sent to ECR is found. This field is “00” by default and indicates that there is not data from GT to return to ECR. A value other than “00” alerts the terminal of:
CURRENTLY THE FIELD IS SET AT “62” |
| 19 | 8 | A | TAG number. Indicates the TAG where data from GT that must be sent to ECR is found. This field is only significant if the previous field is not “00”. The field is flush left, blank justified. TAG from GT length is fixed at 255. CURRENTLY THE FIELD IS FIXED AT ‘DF8D01’ |
| 27 | 1 | N | Reserved (fixed at “0” 30 hex) |
| 28 | 4 | N | Exclusive TAG index with additional data to be sent to GT. The field is considered as a byte map for which each byte corresponds to a single index. “0” corresponds to no TAG to be sent to GT. |
| 32 | 5 | N | Reserved (fixed at “0” 30 hex) |
| 37 | 100-V | A | Privative TAG content. Max 100 characters - Min 1 character. The field is always closed by an end-of-field character 01B hex |
The “Exclusive TAG content” field can be repeated for a maximum of 4 times.
Additional data from GT result message (from Terminal)
The additional data from GT message is only sent by the POS terminal if the ISO number field in the "Message with additional data for GT" is not "00".
| Pos | Length | Type | Content |
|---|---|---|---|
| 1 | 8 | N | Terminal ID (00000000-99999999) |
| 9 | 1 | A | Reserved – fixed to ‘0’ (0x30) |
| 10 | 1 | A | Message code: ‘U’ (0x55) |
| 11 | 6 | N | Reserved (fixed at “0” 30 hex) |
| 17 | 3 | N | Data from GT field length. Indicates the length of the next field |
| 20 | 255-V | A | Additional data from GT that must be sent to ECR |
| 20+n | 10 | N | Reserved (fixed at “0” 30 hex) |
Tokenization Request
The transaction requested to activate tokenization via LAN Integration must include Additional Data, in the format requested for the service, with the following information:
- Type of Tokenization service requested (Recurring, Unscheduled, One Click)
- Contract code: the code has to be unique at Merchant level and is alphanumeric 18 characters long.
Additional TAGs - Intesa San Paolo
| Length | Type | Content |
|---|---|---|
| 4 | An | Identification code of the service:
|
| 4 | An | Fixed value “0TRK” |
| Ans..18 | An | Unique contract code |
| 1 | Ans 1 | “|” (pipe) |
| 4 | An | Service code “Labelling Omnichannel” Fixed code “0FNZ03” |
Example TAG 5 mapping for Unscheduled Recurring and One Click Payments with contract code 1666354841608 Es: 0COF0TRK1666354841608|0FNZ03
TAGs – Other Banks
| Index (TAG) | Position (Byte) | Length | Type | Content |
|---|---|---|---|---|
| 1 | 1 | 3 | A/N | Fixed value “BTD” |
| 4 | Variabile (max 18 bytes) | A/N | Unique contract code | |
| 5 | 1 | 4 | A/N | Identification code of the service:
|
| 5 | 4 | A/N | Fisso a “0FNZ” | |
| 9 | 2 | A/N | Action: “03” – new contract creation |
Example TAGs mapping for Unscheduled Recurring and One Click Payments with contract code 9297022f-75de-48.
| Index (TAG) | Position (Byte) | Length | Type | Content |
|---|---|---|---|---|
| 1 | 1 | 3 | A/N | BTD |
| 4 | Variable | A/N | 9297022f-75de-48 | |
| 5 | 1 | 4 | A/N | 0COF |
| 5 | 5 | 4 | A/N | 0FNZ |
| 5 | 9 | 2 | A/N | 03 |