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The CORBA Object Model identifies various distribution transparencies that must be supported within a single ORB environment,
such as location transparency. Elements of ORB functionality often correspond directly to such transparencies. Interoperability
can be viewed as extending transparencies to span multiple ORBs.
In this architecture a domain is a distinct scope, within which certain common characteristics are exhibited and common rules
are observed over which a distribution transparency is preserved. Thus, interoperability is fundamentally involved with transparently
crossing such domain boundaries.
Domains tend to be either administrative or technological in nature, and need not correspond to the boundaries of an ORB installation.
Administrative domains include naming domains, trust groups, resource management domains and other “run-time? characteristics
of a system. Technology domains identify common protocols, syntaxes and similar “build-time? characteristics. In many cases,
the need for technology domains derives from basic requirements of administrative domains.
Within a single ORB, most domains are likely to have similar scope to that of the ORB itself: common object references, network
addresses, security mechanisms, and more. However, it is possible for there to be multiple domains of the same type supported
by a given ORB: internal representation on different machine types, or security domains. Conversely, a domain may span several
ORBs: similar network addresses may be used by different ORBs, type identifiers may be shared.