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From a computational viewpoint, the OMG Object Model identifies various distribution transparencies which ensure that client
and server objects are presented with a uniform view of a heterogeneous distributed system. From an engineering viewpoint,
however, the system is not wholly uniform. There may be distinctions of location and possibly many others such as processor
architecture, networking mechanisms and data representations. Even when a single ORB implementation is used throughout the
system, local instances may represent distinct, possibly optimized scopes for some aspects of ORB functionality.
Figure 13-1 Different Kinds of Domains can Coexist.
Interoperability, by definition, introduces further distinctions, notably between the scopes associated with each ORB. To
describe both the requirements for interoperability and some of the solutions, this architecture introduces the concept of
domains to describe the scopes and their implications.
Informally, a domain is a set of objects sharing a common characteristic or abiding by common rules. It is a powerful modelling
concept which can simplify the analysis and description of complex systems. There may be many types of domains (e.g., management
domains, naming domains, language domains, and technology domains).