Authorize.net Advanced Integration Method (AIM), uses a transaction key authentication for ultimate security.
This is the preferred method to integrate with Freedom CMS for Commerce.
In order to use the AIM method, first, it must be selected in Green > Toolbar > Commerce configuration. Then on the form used to process totals for payment, it must have a form field with the unique id of 'gateway' and field type 'hidden' to process the transaction.
Authorize.net Server Integration Method (SIM), works a lot like the free version of paypal. Once a Freedom CMS website visitor hits the checkout button from the commerce shopping cart page, they will be re-directed to an Authorize.net payment page (similar to paypal). Once they complete their payment on the Authorize.net page, the visitor will be re-directed to the Freedom CMS website.
There are a few downsides to using the SIM method:
1. You cannot use SIM with one-step checkout forms (Blue > Forms > Web Forms)
2. You cannot collect shipping fees/tax fees setup on the Freedom side, you can only process the subtotal of what is in the shopping cart.
The easiest way to use the SIM method is:
First, it must be selected in Green > Toolbar > Commerce configuration.
Then, on your shopping cart layout (Green > Layouts > Module layouts > edit [Shoppingcart]), add the Authorize.net SIM button in the body section of the layout.