I have worked at many pages for the payment system integration and recently i have completed Google Checkout integration. Its an awesome service from Google. The difference from paypal is, its by default security system (Fraud Protection).
From my observation most of the programmer just implement paypal simple form and after completing the payments they receive the visitors at a page where they show them a Welcome message for making the payments and make the necessary changes to update the tables. Paypal sends user at success page when payments is success and sends to another page when transaction becomes unsuccessful. But to protect the fraud transaction at paypal we need to implement IPN (Instant Payment Notification) technology. The fact is, very few programmers do care this matter. Yes Paypal’s IPN technology is little bit complex (For General Programmer) but i think this is essential when the subject is payment.
Google checkout doesn’t need any additional technology to protect Fraud Transaction. It provides some classes to integrate with my site. It also release the classes for PHP 5. But its documentation is not rich yet (Previous version’s is smart one). Hope within short time documentation will be enough for the programmers.
If you want to take payments (From Credit Card) from your site (Without bringing visitors to merchant’s site) you have to use others service except paypal and Google Checkout. So far i worked on those i got the most easiest system is CyberSource. Though its a new but its awesome. Their documentation is not rich enough but they provide easy integration tools. I have a bad experience with Protx integration. According to integration manual i customize their templates , i placed all the kits into my system but when i asked for Simulation server (Just like Sandbox) my contractor becomes confuse about its purpose. I Just wonder how can someone except a system without testing its accuracy, even when its a matter of Online Payment. Anyways i didn’t complete that integration.
In Bangladesh we can’t use those service, because our country’s bank doesn’t support online international payments. I’ll be the happiest one when i could integrate online payment system for our country’s site. When we can take payments from our site to directly our local bank( Through International Credit Card). I Hope I’ll be able to do that within next few years.
