Integrating SaaS or Cloud applications with on-premise databases may seem straight forward enough at first pass but can be challenging if you don't have the right approach.
Cloud applications like Salesforce.com provide APIs that can easily be used to integrate with your on-premise applications or databases. For example, using MuleSoft's Salesforce.com Cloud Connector, developers can easily set up a process which polls for changes in their Salesforce org and synchronizes the data with a local database instance. The assumption here is that the integration platform is running behind the firewall and is always the one making outbound calls to the Cloud looking for changed data.
What if, you wanted to integrate Cloud data with on-premise applications in an event-driven or near real-time fashion? For Cloud applications to notify your process of data events as they are occurring, they would have to be able to reach it some how. The typical model would be to send a request over HTTPS through your firewall(s) and proxy servers to your process and finally to your application. It's easy enough to configure Salesforce.com, for example, to send out notifications based on data changes using Workflows and Outbound Messages but the security considerations of this approach will dissuade most developers from pursuing it and rightfully so. The process to get security approval, make the firewall policy changes, and place the necessary infrastructure in place is just too hard to deal with, until now!
Mule iON‘s Secure Data Gateway (SDG) provides a secure (as the name suggests) channel to let your Cloud data pass through with very little effort while mitigating risk. The SDG is a very light weight piece of software that is downloaded and installed behind the firewall allowing for a reverse channel over SSL to be opened up to the Cloud from inside-out while letting data pass through from Mule iON to your local applications and databases. This allows you to create a process running on Mule iON which can receive notifications from Salesoforce.com via an Outbound Message (WS request), translate and transform the (XML) request to database calls (over JDBC), and relay them over the SDG to your database. No firewall policy changes, no proxy or web server in the DMZ, and no hassle.
Sign up for Mule iON and follow the Integrating Salesforce.com with an On-Premise Database tutorial to see how easy it can be.
