What is the Cluster ID used for with the Digimesh Modules?

We are using the 2.4 Digimesh modules for an application. I would like to know how the Cluster Id is intended to be used in a Digimesh application. I understand that the 0x11 is the default Cluster ID and the 0x12 provides a loopback service. What other impact does the cluster ID have on the routing of messages and the ability of the modules to communicate with each other?

The Cluster ID is strictly used as a compatibility function with Zigbee applications. This way you can use either Digi Mesh or Zigbee mesh and not have to modify your application.