Centralized data, centralized processing (no networking)
This is the traditional approach to Oracle data, where all the data resides in a common database and all the processing is performed by a centralized computer, usually a large UNIX server.
This approach has the advantage of better control of the Oracle data, but has the disadvantage of being subject to widespread performance degradation when the CPU becomes overloaded.
Because there is also a single point of failure , which is CPU of the Unix machine, the probability of experiencing downtime is increased. If this single CPU would fail, this problem could cripple the entire system, making access to the data impossible.
For this reason it is better to focus on a solution that involves distributed networks.
A distributed network would enable the data as well as the CPU to be de-centralized, thus preventing the possibility of hardware or database failure.
A centralised database (sometimes abbreviated CDB) is a database that is located, stored, and maintained in a single location. This location is most often a central computer or database system, for example a desktop or server CPU, or a mainframe computer.
In most cases, a centralised database would be used by an organisation (for example a business company) or an institution.
Users access a centralised database through a computer network which is able to give them access to the central CPU, which in turn maintains to the database itself. All of the information stored on the CBS is accessible from a large number of different points, which in turn creates a significant amount of both advantages and disadvantages.