> For the complete documentation index, see [llms.txt](https://docs.coda.co/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.coda.co/codapay/direct-api-integration/direct-api-integration-for-alternative-payment-methods/backend-call-flows-brief.md).

# Backend Call Flows Brief

## Direct Carrier Billing (DCB)

**Direct Carrier Billing (DCB)** is a payment method that allows customers to charge purchases directly to their mobile phone accounts. The payment is authenticated via an SMS sent to the customer's device, ensuring secure and immediate transaction processing. 

The authorization process may vary depending on the payment channel, and the information required from customers can differ accordingly.

## E-Wallet

With the E-Wallet payment method, partners receive a redirect link that allows customers to complete their transactions. This link may either open the E-Wallet app directly (deep link) or lead to a redirection page where customers must enter additional details and authorize the payment.

## Bank Transfer

Customers can complete their payment by making a bank transfer through an ATM, at a bank counter, or via online banking. Partners receive a unique payment code in the profile field, which the customer must enter as part of the transfer details.

## Card Payments

The card payment option enables customers to pay using their credit or debit cards. They are redirected to the partner's payment page, where they enter their card details, including the card number, expiry date, and CVV code, to complete the transaction. Codapay records payments in real-time, ensuring that partners receive immediate notifications upon successful payment.

## Vouchers (Cash Card)

With the voucher payment method, customers redeem their voucher codes through Codapay. Payments are registered in real-time, and partners receive immediate notifications upon successful redemption. The voucher's value is confirmed only after redemption, so partners must validate the net amount returned in Coda's API response and manage the redemption process for all available denominations.

## Convenience Store (OTC)

The convenience store payment option allows customers to complete their transactions at a convenience store or a designated payment counter. Partners receive a unique payment code in the profile field, which the customer must present at the counter to process the payment.

{% hint style="success" %}
**"resultCode": 0** means transaction success
{% endhint %}


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