COMMUNICATIONS STRUCTURE MODELING

  Communications structure modelling is performed via Communicating Objects (CO) diagrams.
  In the previous versions such diagrams were called as CD diagrams.
  CO diagrams describe the static structure of a model and are used to represent both the division of objects into smaller subobjects and the communication between them.
The diagram may contain the following elements :

	Object	Represents an independently acting part of an enterprise which can communicate with other such parts. An object may be refined further via another CO diagram or represented as a process described by a PD diagram.
	Internal Communication Path	Links two objects and signifies that messages are transmitted from one object to another in the specified direction.
	External Communication Path	Represents a communication path which is continued in the CO diagram on a higher level.
	Database	Represents a persistent data store whose structure is described by an entity-relationship model.
	Internal Access Path	Connects object to a database. The following access paths are available: IN (object can only read data from the database) OUT (object only adds data to the database) INOUT (both types of access are permitted)