Understanding the payment flows for processing transactions through Solidgate is crucial for ensuring a smooth integration.
Auth + Settle
This process involves the merchant obtaining authorization to hold a customer’s funds, Solidgate communicating with the acquirer to process the transaction, and the merchant settling the transaction. Effective communication between Solidgate, the acquirer, and the merchant is crucial in ensuring a successful transaction.

- The merchant requests
auth
to hold the customer's funds, specifying the hold duration in hours. The merchant either specifies asettle_interval
for auto-settlement or intends to manually settle at a later point. - Solidgate acknowledges receipt and forwards the request to the acquirer for determination of
auth
approval. - Solidgate receives the
auth
response from the acquirer. - Solidgate processes the
auth
response and sends a callback request with transaction status to the merchant. - The merchant confirms receipt of the
auth
status to Solidgate. - After the specified time interval
settle_interval
, Solidgate requests the acquirer to settle the transaction. The merchant can initiate partial settlement before the time interval expires, which results in the automaticvoid
of the remaining hold amount. - The acquirer returns a
settle
response to Solidgate, confirming the transaction settlement. - Solidgate processes the
settle
response and sends it to the merchant via a callback request. - The merchant confirms receipt of the transaction status to Solidgate.
3DS
This process is designed to enable secure and reliable payment processing through the use of 3D Secure (3DS) with challenge authentication flow.
Authentication in the context of 3D Secure is the process of confirming that the person making an e-commerce transaction is entitled to use the payment card.
3D Secure 2, the latest version of the protocol, defines two types of authentication flows:
-
Frictionless flow
This is the process of authentication achieved without Cardholder interaction. It streamlines the transaction process by minimizing user input, provided the transaction is deemed low-risk or meets certain criteria set by the issuing bank. -
Challenge flow
If the ACS (Access Control Server - a component that operates in the Issuer Domain) determines that further Cardholder interaction is required to complete the authentication, the Frictionless Flow transitions into the Challenge Flow. This additional step may be necessary in situations where the transaction is deemed high-risk, exceeds certain thresholds, or requires a higher level of authentication due to country mandates or regulations. In such cases, 3DS Requestors (merchants or their acquiring banks) must decide whether to proceed with the challenge or to terminate the 3-D Secure authentication process.

- The merchant collects card details from the cardholder. They can send a request (
auth
orcharge
) to Solidgate. Concurrently, they have the option to request 3DS authentication by setting theforce3DS:true
parameter in the request. - Upon receipt, Solidgate confirms the request. If the merchant requested 3DS authentication, Solidgate defaults to the 3DS flow.
- Solidgate sends a 3DS request to the acquiring bank. If the transaction is executable, the acquiring bank returns the ACS (Access Control Server) URL to Solidgate.
- Solidgate forwards a
verify_url
embedded with the ACS URL to the merchant. - When the client accesses this URL, Solidgate receives the verification request.
- After the client interacts with the 3DS page, the merchant sends a 3DS request to Solidgate.
- Solidgate then requests the 3DS check status from the acquiring bank.
- The acquiring bank returns a verification response to Solidgate, indicating whether the transaction is approved or declined.
- Solidgate processes the verification response and initiates a callback request, providing the transaction status to the merchant.
- The merchant takes necessary steps and confirms to Solidgate the receipt of the transaction status.
Void
The process involves the merchant obtaining authorization to hold the Customer’s funds and initiating a void
operation if needed. Effective communication between Solidgate, the acquirer, and the merchant is crucial in ensuring a successful transaction.

- The merchant requests
auth
to hold the customer's funds. - Solidgate acknowledges receipt and forwards the request to the acquirer for determination of
auth
approval. - Solidgate receives the
auth
response from the acquirer. - Solidgate processes the
auth
response and sends a callback request with transaction status to the merchant. - The merchant confirms receipt of the
auth
status to Solidgate. - To initiate the
void
operation, the merchant sends avoid
request to Solidgate. - Solidgate acknowledges receipt and forwards the
void
request to the acquirer. - The acquirer returns a
void
response to Solidgate, indicating whether the transaction is declined or approved. - Solidgate processes the
void
response and sends it to the merchant via the callback request. - The merchant confirms receipt of the transaction status to Solidgate.
Refund
The refund process involves communication and coordination between the merchant, Solidgate, and the acquirer to ensure the refund is processed successfully.

- The merchant submits a refund request to Solidgate.
- Solidgate acknowledges receipt and forwards the request to the acquirer for determination of refund eligibility.
- The acquirer returns a refund response to Solidgate, indicating approval or denial of the refund.
- Solidgate processes the refund response and sends a callback request with the transaction status to the merchant.
- The merchant takes necessary actions and confirms receipt of the refund status to Solidgate.
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