Preallocated Reference Transactions

This document is a technical introduction to the Preallocated Reference Transactions Service. It assumes the reader has some familiarity with the Card Holder Present service. Further detailed information to assist integration with the Service is available in the Developers Guide.

This Service enables a reference number to be allocated on the DataCash Payment Gateway (DPG) for a transaction before the payment details are submitted to DataCash. This means that once the payment details are submitted to the DPG, if a communication error prevents you from receiving any response, you may use the allocated reference number to check on the status of the transaction using the Reporting facility, or to automatically cancel the payment.

This service may only be used for Card Holder Present transactions.

Requirements

Before you can go live with Preallocated Reference transactionsyou will need the following:

  • An account set up with DataCash, configured with the CHP service
  • The ability to send XML transactions to the DPG

Transaction Processing Models

Using this service, an initial allocate_reference transaction is submitted to DataCash.

Transaction Type Effect Uses
allocate_reference Generates a datacash reference Enables any subsequent payment request to be cancelled, even if the result of the payment is not known

When the payment is submitted using the allocated reference, it can be processed as either a creditcheck or an auth transaction type - in exactly the same way as for normal Chip and PIN transactions.

The payments may be cancelled if required using the allocated reference.

Performing Transactions

In addition to the fields listed below, all transactions must contain a client and a password field for authentication purposes.

Allocate Reference

In addition to the standard fields mentioned above, you mustprovide the following information when preallocating a reference:

  • The transaction type allocate_reference
  • A unique reference number generated by your system - to allow the transactions to be distinguished from each other

Once allocated, a reference must be used within five minutes orelse it will expire.

Taking Payments with an Allocated Reference

When taking a payment using a pre-allocated reference, exactly the same information must be presented as for the Chip and PIN service, with the allocated reference number taking the place of the reference number

Cancelling Transactions

Cancellations and reversals of the transactions using this Service are performed in exactly the same way as for a normal Chip and PIN transaction.

Return Codes

The basic return codes for transactions remain the same as for the Chip and PIN Service

In addition there are various error codes that can be produced specifically by this service.

The Support Centre also contains extensive examples for most error codes. Illustrations and suggestions are given to help you prevent them from occurring.

Reporting

All transactions performed using this service will appear in the Bank Card section of Reporting. There are three main pages:

  • Summary - gives a summary of the transactions
  • List - shows specific details of the transactions
  • Details - shows full details of each transaction. This page will not be available for any unused preallocated references

The Support Centre contains full hints and tips to help you get the most out of Reporting.