Offline Stand-in

IPC can accept payments even when it is off-line.

Normal online process

To accept sales transactions, IPC uses the IPC POS central service to contact the card issuer.

From the card issuer IPC gets an approval code, called the authorisation code. This authorisation code allows the transaction to be processed; this is called an online authorisation. For online authorisation to work, IPC must have Internet access. IPC must also contact the Integrated POS service at the start of every transaction.

IPC needs a URL to contact the Integrated POS service; there are two URLs available, a primary URL and a secondary URL.

If IPC cannot contact either the primary or secondary URL, you must process the sale in a different way. This is the offline acceptance process.

Telephone authorisation

If IPC cannot connect with either URL, IPC automatically displays a referral prompt to the payment terminal attendant.

This referral prompt asks for voice authorisation and gives the telephone number of the Worldpay contact centre to call. To accept the transaction, the payment terminal attendant enters the voice authorisation code from the Worldpay contact centre. Alternatively, the payment terminal attendant can reject the transaction and the transaction is cancelled.

Offline Stand-In

IPC also offers an option to accept sale transactions locally, up to a pre-defined value. This is called Offline Stand-In, or simply Stand-In.

Stand-In is useful if the payment terminal has lost connection to the Integrated POS service and cannot send transactions online for authorisation. This feature is called Offline Stand-In mode and is enabled at the Integrated POS service.

If Offline Stand-In mode is enabled, IPC automatically switches to Offline Stand-in mode if it cannot contact either the primary or secondary URL. When it is in Offline Stand-In mode, IPC accepts chip sale transactions up to an agreed value.

Note: Some card schemes such as International Maestro and Electron, do not allow offline acceptance.

You cannot accept offline contactless sale transactions and offline magnetic swipe sale transactions. For these types of offline transactions, including chip transactions that are above the value of the pre-defined limit, IPC displays a referral prompt.

This referral prompt asks for voice authorisation and shows the telephone number of the Worldpay contact centre to call. To accept the transaction, the payment terminal attendant enters the voice authorisation code from the Worldpay contact centre. Alternatively, the payment terminal attendant can reject the transaction and the transaction is cancelled.

IPC automatically switches out of Stand-in mode at the next transaction when it can contact either the primary or secondary url.

To enable the Stand-in mode feature, contact Worldpay Support or your Worldpay Relationship Manager (RM).

Warning: You, the merchant, carry the risk and liability of any chargebacks and consequences associated with "Stand-In-Mode" transactions. This only applies if these transactions have not been sent online to the issuer.

Locally stored transactions

When IPC operates offline, it uses the local IPC folder to store the details of transactions it has accepted locally. Sensitive transaction data is encrypted in the payment terminal and you, the merchant, have no access to the encryption keys.

Remember that IPC can store transaction data locally, even if stand-in mode is not enabled. For example, most refund transactions do not require authorisation from the issuer and are accepted offline. Normally IPC uploads these transactions to the Integrated POS service as part of the normal transaction flow. But if IPC cannot contact the primary or secondary urls, it stores the transactions locally.

You can select the number of offline transactions that are allowed to accumulate in the local store. You control the number by a configurable parameter.

IPC runs an internal process every 10 minutes to check if there are any locally stored transactions. If it finds local transactions it connects to the IPC POS central service and uploads the transactions to Worldpay. This is how it empties the local store.

Data loss may occur if the payment terminal hardware suffers irrecoverable failure when there are transactions stored in the IPC local store. We recommended that you back up the IPC local storage file at regular intervals. This should prevent any potential loss of transaction data.