Nortel INM 4.1, Руководство по планированию

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INM Broadband 4.1 Planning Guide PG OC 98-13 Issue 1.2
Inspired by the technological and architectural advances made, the next
generation of OSSs are rapidly evolving toward highly distributed multi-
vendor systems, with open interfaces, and applications that are independent
from the underlying transport technologies. The fundamental driver for this
migration is the need to develop and deploy highly scalable new services in a
rapid and cost-effective manner.
As such, in order to capitalize on the synergistic aspects of the two
architectures (TMN and CORBA), it is highly desirable to employ CORBA
services in a rapid and cost-effective manner to provide TMN compliant
applications that offer open and standard compliant interfaces.
Application structure and principles of CORBA
Network management applications are distributed applications. In the CORBA
architecture, which is based on object-orientation methodology, a distributed
application is composed of objects that interact with each other. In general an
object is an abstraction of a resource, concept, or functionality that provides a
set of capabilities for other objects. In practice a CORBA object is more
viewed as a means to model an application entity. More precisely, a CORBA
object is described as “a package of data and code used to implement a
computational construct or to model an application entity”.
To enable other objects to access its capabilities, a CORBA object offers a
single interface, however the interface may inherit from other interfaces. Each
interface defines a set of operations (function calls) that can be invoked via the
interface.
The object that provides the interface is called the object implementation in
CORBA, and the object that invokes operations defined in the interface is
called a client. The terms “Client” and “Server” are used frequently in Corba
to describe the Peer-Peer relationship that exists between the two entities.
Servers contain one or more objects, and are often physically represented as
processes. Objects, not servers are invokable. An object in a server can be
invoked by a client, and this object can use the facilities of other objects in the
system. A CORBA server/executable which groups several CORBA objects
providing services in an application domain may be termed as a “building
block”.
An object’s interface is defined in OMG’s Interface Definition Language
(IDL). IDL is not a programming language. An IDL only defines interfaces,
where each interface definition lists the operations that can be applied to
objects with that interface. In other words, the IDL interface specifies all of the
operations the object is going to perform, their input and output parameters and
return values, and every exception that may be generated.