Preventing network issues
When you make a point of sale transaction, your cash register, terminal, and Adyen will need to be able to communicate with one another.
For networking requirements, and our recommendations on how to configure your network, see our network configuration documentation.
Handling network issues
There are several ways you can continue making transactions when your primary internet connection is unavailable. These are:
- Use a 3G/4G failover connection. When your primary internet connection fails, transactions are processed using the cellular connection.
Enable offline transactions. This will allow you to continue processing transactions when your store has no internet connection.
Offline transactions are only available for integrations that use local communications.
Using 3G/4G failover
To use a cellular connection as a backup, you can either:
Using 3G/4G terminals
The Verifone V400m and e285 terminals have built-in 3G/4G hardware and pre-installed SIM cards. If your primary internet connection drops, these terminals will automatically switch to processing payments using the 3G/4G connection. They will also switch back to using your primary internet connection once this is available again.
To enable a 3G/4G terminal connection, contact our POS Support Team. There is an additional monthly cost for using this service.
Using a 3G/4G router
If your terminals don't have built-in cellular hardware, we recommend installing a router with 3G/4G network failover. To ensure you get the best cellular reception, you should also install external 3G/4G antennas.
If your integration uses local communications, you are able to continue making transactions without an internet connection. There are two types of transaction you can make in this situation:
Offline EMV: Supported by some credit cards. For offline EMV transactions, the terminal needs to perform some verification on the card's EMV chip before a transaction is approved.
- Store-and-forward: Supported by almost all other credit, debit, and pre-paid cards. The transaction is approved without the terminal performing any verification. The risk that the payment is declined is higher than for Offline EMV transactions.
Once your integration is online again, authorised transactions are automatically forwarded to card issuers for processing.
Offline transactions are riskier than online transactions, and have a higher risk of chargebacks, disputes, and failed captures and settlements. If you process transactions offline, you are fully liable for these risks.
Generating compliant receipts
Card schemes have very specific requirements on what should be included on a receipt. These requirements differ per scheme and country, and can change. Receipts generated by Adyen have been certified as compliant by the card schemes that we support.
We strongly recommend generating receipts using the Adyen-generated receipt data, without alterations.
Card schemes will occasionally visit stores to verify that receipts being generated are fully-compliant. Non-compliant receipts can result in payments being charged back.
If you override this receipt data, or validate values against a hard-coded list, it is your responsibility to ensure that scheme requirements are met at all times.
For more information, see our point of sale receipts documentation.