My colleague Andy Orrock wrote a blog post titled “Now, you’re the switch” where he summarizes challeges and witness poor implementions of some interfaces that we connect to:

But here’s the thing: once we send the transaction to you, now you’re the switch.  What I mean by that is:  your application is now beholden to the same throughput, speed, efficiency, extensibility and 24×7x365 availability concerns that define our lives.  And while there have been many that have been up to the task, there have been countless other instances where that’s not been the case.

There are are few basic models that we have seen that work well:

1. OLS Implemented Business Logic based on customer developed prototypes.
2. OLS Implemented Business Logic and Customer provided Database or Flat File update feeds that drive authorization decisions. 
3. OLS Transaction Participants that call Customer Provided Software and CustomerSecretSauceManger.process() methods within our processing framework.
4. Under our guidance, interface remotely to an local endpoint via TCP/IP Sockets or WebServices, handling concerns that we address here with tech savvy customers.

Possibly Related Posts (automatically generated):

1. CaseSwitch – Source Port Routing
2. Swiping the Card at a Customer’s location
3. Pre-Authorization data for completions and reversals and removal of Track II Data
4. Velocity Manager and Velocity Profiles