A TIBCO iProcess Engine installation on one server is known as a TIBCO iProcess Engine node. All the iProcess Engine processes are run on a single server.
Installing the TIBCO iProcess Engine on multiple servers that all use the same database instance is known as a node cluster architecture. You can convert from a single-server to a node cluster at any time simply by adding another server to the installation. In the node cluster architecture, you can have a number of TIBCO iProcess Engine processes running on different servers, but they act as though they are a single iProcess Engine. Node clusters improve load balancing and performance. However, all the TIBCO iProcess Engine case data such as fields and their values in forms will be stored in one TIBCO iProcess Engine database instance.
Refer to Network Communication for more information about TIBCO iProcess Workspace and TIBCO iProcess Engine communication.