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A real database, with all the data management, control, and maintenance capabilities typically a part of a real data base management system, is essential to the operation of an
enterprise-wide system.
Oracle® is the database incorporated into EnterpriseSMS. Oracle manages all of the information required to configure and operate the
EnterpriseSMS software. Further, the database is the repository of all activity recorded by the system. A Database Support Module
(DSM) contains at least one data base kernel with appropriate data tables called an "instance", a variety of Oracle support tools and
interfaces, and a collection of programs that provide interface with other EnterpriseSMS modules. Oracle is the world leader in RDBMS
(Relational Data Base Management System) technology, and supports all features found in lesser databases. Oracle is a truly open data base product.
There are several types of Database Support Modules in the category. These modules differ in their approach to sharing data. The
different DSM modules are the Simplex DSM, the Redundant DSM, and the Host-Subhost DSM.
A simplex data base module operates on a fully independent basis and only shares data with software modules outside than the Database
Support Module category. Most EnterpriseSMS systems only have a single data base. A simplex module contains a single Oracle kernel and
"instance" of the EnterpriseSMS data tables.
Redundant systems utilize a Redundant DSM (also called "multi-master" or "symmetrically replicated"). A Redundant DSM is
composed of two equal, independent, simplex data base modules synchronized by an additional layer of configuration software which
ensures their continuous synchronization over a network connection. When the connection between them is lost, both operate
independently and resynchronize upon recovery of the connection between them. A redundant database support module provides for
symmetric replication of data; that is, both underlying databases are synchronized when they are identical.
Host-Subhost database modules are more complicated because they support asymmetric replication of data between different instances.
In these cases, the data is not replicated equally from one data base instance to another in order to achieve some specific system
capabilities. The configuration of these systems is always a special, custom effort and the layer of configuration software is not standard
for Host-Subhost DSM. However, the Oracle kernels and EnterpriseSMS instances are identical in structure to those elements in other DSMs.
Several important observations should be drawn from the above:
The basic building blocks of a database support module are the Oracle data base kernel and an instance of EnterpriseSMS data
tables. The different DSMs (Simplex, Redundant, Host-Subhost) differs in the number of incorporated Oracle
kernels and instances of EnterpriseSMS data tables, and the configuration software used to achieve replication and synchronization.
The construction of the DSM from standard program components (kernel, instance, configuration software, Oracle
tools) simplifies management of the EnterpriseSMS system. This design approach locates data in a standard component so
that export and protection of the data export preserves the user's ability to recover the system to the point in time of the
data base export. The data in the instance is independent of the configuration of a particular system. Thus, the system is
easily upgraded as new features become available.
The only connection requirement between DSM components is that they be network connectable. Thus, they may be
physically installed on any suitable server or workstation with a suitable network connection.
Every EnterpriseSMS system requires at least one database support module to be operable.
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