Payment Service provider API ISO8583_2 ( IFSF) H2H description
OVERVIEW
The purpose of the H2H PayEx link is to enable authorization and settlement of card transactions, where PayEx is end host for that card, or just an PSP. The third party host acts as a gateway in between payment terminals and PayEx.
- The third party host can be a single or dual host system.
- PayEx has a fully redundant system, with an active/active configuration.
- The third party host(s) connect to PayEx loadbalanser
MESSAGE LAYOUT
This section covers message types and fields supported by PayEx
GENERAL
Presence | Title | Description |
C | Conditional | The data element’s presence depends on specific circumstances. The circumstance is defined either directly or by reference to another section of the document |
CE | Conditional echo | The response message must have the same data element if the data element is present in the original message |
M | Mandatory | Data element must be present in the specified message |
ME | Mandatory echo | The response message must have the same data element and value as sent in the original message request or advice message. |
O | Optional | The data element may or may not be present in the message. |
Requests received missing a mandatory field will be 904 - Format Error.
Optional fields may always be present in requests, even when not needed. In such case, they will be ignored.
The third party host must ignore unknown fields included in the response messages.
When no usage notes are given in the field description, the field should be used as described in IFSF [1].
The “Format”-column can contain following info:
- LL: Variable length field, max 99 bytes as data. The field contains 2 bytes holding the length of the data. Example: 303101 a one byte field with LL = 3031 and the data is 01.
- Date/time field formats, YYMMDDhhmmss (or variations), where:
- YY : Last 2 digits of the year, 00 through 99
- MM: Month, 01 through 12.
- DD: Day, 01 through 31
- hh: Hour, 00 through 23
- mm: Minutes, 00 through 59
- ss: Seconds, 00 through 59
- LLL: Variable length field, max 999 bytes as data. The field contains 3 bytes holding the length of the data. Example: 30303101 a one byte field with LLL = 303031 and the data is 01.
- Date/time field formats, YYMMDDhhmmss (or variations), where:
The “Type”-column can contain:
- a : Alphabetic character [a..z,A..Z]
- n : Numeric BCD-digit. [0..9]
- ans: alphabetic, numeric and special characters
- an : alphabetic and numeric.
- s : Special characters.
- b : Binary
- p: pad character, space
- x: “C” for credit, “D” for debit and shall always be associated with a numerical amount data element.
The “Size”-column can contain:
- Variable length fields have a size that looks like “..nn”, where nn is the maximum number of characters or bytes.
- A fixed length field has “n” as size content, with n the number of characters or bytes.
All fixed length “n” data elements are assumed to be right justified with leading zeroes. All other fixed length data elements are left justified with trailing spaces. In all “b” data elements, blocks of 8 bits are assumed to be left justified with trailing zeroes.
For technical reasons an advice can be declined if PayEx is unable to store the transaction. In this case the third party host need to retry the advice until manual intervention or the advice has been accepted. It’s expected that the third party implement a retry delay (to-be-defined). After 6 retry attemps have failed manual intervention by thirsd party and PayEx support must be initiated.
Message authentication is performed on network management requests to validate the MAC key issued by PayEx, and by the third patry to validate that the PayEx system is running as expected. Implementation of this message type is not mandatory.
ata element name
INDOOR TRANSACTIONS
TO-DO create a REVERSAL ADVICE 1420/1421/1430 page and link to it - if this differe with inndoor reversal advice