Nodes

A node represents a computational resource that generally has memory and often has processing capability.

The notation for a node is a cube. The name of the node always appears on the cube; optionally , a list of the components that reside on that node also appears. Figure 9-9 shows two example nodes, connected with a communication path , which is comparable to an association between classes (see the section "Associations" in Chapter 2).

Figure 9-9: Nodes

The UML defines the following two specific kinds of nodes:

• A device is a physical computational resource with processing capability upon which artifacts may be deployed for execution. Figure 9-10 shows two example devices. (Listing the components that reside on the device is optional.)

  
  Figure 9-10: Devices

  A device may also contain other devices via a composition relationship (see the section "Aggregation" in Chapter 2).

• An execution environment offers an environment for the execution of specific types of components that are deployed on the environment, in the form of executable artifacts. Figure 9-11 shows an example of an execution environment.

  
  Figure 9-11: Execution environment