US merchants implementing Paypal PayFlow Pro can enroll in the Verified by Visa program.
This is a slightly more complicated than other payment processing systems we offer, in that the credit card transaction takes place on your own server, and hence you require an SSL certificate on your site.
Enabling Payflow Pro will force the second phase of checkout to
take place on a secure (https) connection. For instance, with Payflow
Pro enabled, you will find that after viewing the contents of the
cart and clicking checkout, the URL changes from
If you do not yet have a certificate installed this will fail. To purchase an SSL certificate we can recommend www.thawte.com.
Now you just need to enter the information that PayPal provided you with when you opened your account by going to your store admin and clicking on Edit Payment Providers, and you should be all set.
Please note that it is possible to use shared SSL space if your
host provides for this, but you must be able to access the same
database as for the rest of your store. To do this, you need to
copy at least these files to your shared SSL space . . .
. . . plus probably your images directory.
Then set the pathtossl as above to the directory that contains these files. For instance
pathtossl = "https://www.yourhost.com/yourdirectory/"
We have provided more information about setting up on a secure server here
Please do read our guide here on credit card fraud.