Exchange of data between applications that are not located within organisational trusted zone. It is possible that applications are within the same hosted environment (or cloud) or in disparate environments.
This scenario covers the exchange of data between applications that are hosted in the cloud. This includes applications providing capability as 'Software as a Service' (SaaS) that are co-located in the same environment or in different environments. The scope does not cover integration between internal components of a SaaS offering.
All integration patterns identified in this guide apply. It is important to establish whether the integration requirement should be treated as an Internal or External integration, and then use the rest of this patterns guide to determine the pattern that best fits the requirement. See the "Policy on Internal Integration" and "Policy on External Integration" for details. If the two applications are in the same datacenter or there is a secured private network between the two datacenters, the integration requirement can be considered as internal integration, and in all other cases, the requirement should be considered external.
The integration requirement must be catalogued in the integration catalogue, and may be implemented using the vendor's integration platform. If the vendor has no integration platform, then consider using the organisational integration platform as advised in the policy and the patterns guide.
Integration between an application (eg Oracle Fusion ERP) supplied as a SaaS solution has requirements to connect to a bank to make payments. The bank's application is external to the hosting environment for the SaaS platform. In this example, the integration must be treated as an external integration. The vendor's own platform may be used to facilitate the requirement.