Payment gateway

A payment gateway is an e-commerce application service provider service that authorizes payments for e-businesses, online retailers, bricks and clicks, or traditional brick and mortar. Paypal and SecurePay are two common payment gateways. Following are the list of gateways.

http://www.paymentgatewaydirectory.com/

In our project we use saferpay payment gateway. In billing-services.xml,
< bean id="billing.paymentService"
class="com.fastsearch.admomentum.billing.service.DefaultPaymentService">
. . .
< !-- this bean is defined in fast-admomentum-paymentgateway.jar -->
< property name="paymentGateway" ref="saferpayPaymentGateway" />
. . .
< /bean>

and in base-configuration.properties, there are lots of configurations.
one of them are,

# The merchant account id with Saferpay
com.fastsearch.admomentum.paymentgateway.saferpay.accountId=XXXXX-XXXXXXXXX