Payment Gateway

What is a payment gateway?

A Payment Gateway is a place on your website (or a part of visitor workflow on your website), where a transaction can be made. It’s basically like a cashier’s desk. But instead of you being physically present to handle the transaction, your website does the job for you.

Whether you have an online-store, event management, a travel website, or any website which would involve visitors making online transactions, you would need a payment gateway. So, when people say payment gateway, you immediately think of a service like PayPal or Authorize.Net. But these are not payment gateways, but payment gateway service providers.

Since payment gateways handle very important transactions on your site, you want to ensure that everything happens seamlessly. So, in this article, I’ll be discussing 4 types of payment gateway integration, so that you can be well aware of the different options and make an optimal selection.

  • Simple Checkout Method. (Offsite Payment)
  • Direct Post Method.
  • Server Integration method.
  • Advanced Integration Method.

Simple Checkout Method – Offsite Payment

A very basic integration method is the ‘Simple Checkout Method’. In this method, the payment gateway is integrated as an external service. When a customer clicks the ‘Buy Now’ or ‘Purchase’ button on your site, he or she is redirected to the payment gateway service provider’s website, for example, PayPal, Authorize.Net, PayU, etc, to make a secure transaction. This is the easiest method to integrate a payment gateway into any site.


  • Your website does not need to be PCI compliant
  • You do not need to maintain the payment gateway
  • There are no security concerns


  • A customer has to leave your site to make the payment
  • Sometimes due to a network error, a customer might not be redirected to your site after the payment
  • Such a method is prone to man-in-the-middle attack (eavesdropping)

When to use the Simple Checkout Method?

Simple Checkout is a perfect solution for small private businesses, such as a home-owned business or paid survey forms, paid subscriptions, etc.

How to integrate the Simple Checkout Method for your WordPress website?

You’ll find that most small business websites offer this method. Usually, many WordPress plugins which include payments, such as WooCommerce, Event Espresso, Ultimate Auction, etc, have simple checkout methods integrated into the plugin. For your WordPress website, you could also use a standalone plugin like PayPal Shopping Cart, or a similar plugin for other payment gateway service providers.

Direct Post Method – Transparent Redirect

The next integration method is ‘Direct Post’. In this method the form which accepts the customer information and payment details is served from your web server however, the details are forwarded to the secure payment gateway, where the eventual transaction is handled. Customer data is not handled on your website.


  • Branding is maintained
  • You do not need a PCI compliant website


  • The transaction is not completely secure and could be compromised

When to Use the Direct Post Method?

Direct Post method can be used to improve the branding of your business in a transaction workflow.

How to Integrate the Direct Post Method for your WordPress website?

The Direct Post Method can be integrated using available plugins in WordPress like for WooCommerce there are DPM and PayPal

Server Integration Method – Onsite Payment

Another method is the ‘Server Integration Method’ or SIM. This method provides you the option to handle transactions on your site, even though a payment gateway service provider will handle the actual processing. What happens is, all the forms are displayed on your site. The payment gateway service provider handles all the steps (the payment data collection, data submission and the response to the customer) in the secure transaction process, but the customer is not made aware of this. This allows a merchant like you, to style the look and feel of the payment form and the receipt page.


  • Full control over transaction
  • Connection to Payment Gateway needs to be made only once


  • You will need an SSL certificate

When to Use the Advanced Integration Method?

The advanced integration method is used by enterprise-level businesses, although that doesn’t mean you could not incorporate it on your site

How to Integrate the AIM for your WordPress website?

To integrate AIM for your website, advanced scripting technique knowledge is required. However, you can hunt for plugins too. For WooCommerce, there is the AIM plugin to add AIM for Authorize.Net.

Our team of professional web developers has integrated many websites with leading payment gateways and can integrate any payment gateway of your choice to your e-commerce website that enables you to accept credit card and electronic check payments very easily.  If you need to add the online payment to website or develop a larger web application with multiple features, Contact Us or drop us a line at

Author :Chaitanya Pedagada – Module Lead
Source :

Share This Information