Payment processors

A payment processor is a company (often a third party) appointed by a merchant to handle transactions from various channels such as credit cards and debit cards for merchant acquiring banks. They are usually broken down into two types: front-end and back-end.

Front-end processors have connections to various card associations and supply authorization and settlement services to the merchant banks’ merchants. Back-end processors accept settlements from front-end processors and, via The Federal Reserve Bank for example, move the money from the issuing bank to the merchant bank.

In an operation that will usually take a few seconds, the payment processor will both check the details received by forwarding them to the respective card’s issuing bank or card association for verification, and also carry out a series of anti-fraud measures against the transaction.

Additional parameters, including the card’s country of issue and its previous payment history, are also used to gauge the probability of the transaction being approved.

Once the payment processor has received confirmation that the credit card details have been verified, the information will be relayed back via the payment gateway to the merchant, who will then complete the payment transaction. If verification is denied by the card association, the payment processor will relay the information to the merchant, who will then decline the transaction.

See the list of online payment gateways

In the 16th century, paper currency became a way to trade commodity resources, like tobacco leaves stored in a warehouse. A producer would deposit his crop with the depot, and the depot-keeper would give a bearer-demand note to the depositor which he could trade on the open market for other goods and services.

Due to the many regulatory requirements levied on businesses, the modern payment processor is usually partnered with merchants through a concept known as software-as-a-service (SaaS). SaaS payment processors offer a single, regulatory-compliant electronic portal that enables a merchant to scan checks (often called remote deposit capture or RDC), process single and recurring credit card payments (without the merchant storing the card data at the merchant site), process single and recurring ACH and cash transactions, process remittances and Web payments. These cloud-based features occur regardless of origination through the payment processor's integrated receivables management platform. This results in cost reductions, accelerated time-to-market, and improved transaction processing quality.

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Wikipedia