Before anyone wonders, this isn't the big secret feature that's coming soon, just an evolution of what already exists, it does however tie in nicely with that coming feature.
This will soon be integrated with the cashtobtc system, but we now have a proper IPN (Instant Payment Notification) system with cryptographic authentication via SHA512-HMAC. This should be considered beta-stage at present but it is suitable for those already using the /cashtobtc system
Essentially, you can now use our API to do the following:
1 - Setup a quote with GetQuote()
2 - Subscribe to events on that quote with SubscribeEvents (this is entirely optional)
3 - Subscribe to order executed events only and get sent a signed IPN with SetOrderIPN
4 - Send a customer of yours to https://www.bitinstant.com/quote/
5 - Let your customer pay, receive funds at any of our supported destinations as your customer pays with any of our supported payment methods (this will soon be setup to run smoothly like a checkout page, allowing the customer to choose payment method)
6 - Customer pays, you get confirmation email and an IPN to your website at the URL specified
7 - Optionally (though highly recommended) verify the IPN against the BitInstant API
8 - Send the product you're selling
This was a requested feature for some of our clients who wanted a means to make use of the cashtobtc system in a secure manner without having to watch the blockchain.
Resends are not implemented at present so please ensure your webserver is reliable and do not assume lack of payment if you miss the IPN due to a temporary failure - we will soon add the facility to auto-resend IPNs.
Documentation as always is at https://www.bitinstant.com/api