ABSTRACT
Distributed databases are the charm of today's technological evolution as they arc
being used in almost every field of life: c-banking, mobile, cloud computing. and
various industries. Among others, data replication is one of the core of
distributed database systems which make objects available to more than two
database servers by physically copying objects stored in one to other
database. Replication is synchronous • master/%laves databases need not to be
connected permanently to receive updates from the master. means that updates
can occur over long-distance connections and even over temporary or intermittent
connections such as a dial-up service. Depending on the configuration, you can
replicate all databases, selected databases, or even selected tables within a database.
This research work presents the results from an application based on master-master
synchronous database replication that allows platform heterogeneity. 'I Tie proposed
approach is expected to be tolerant to faults as the data will always be available even
in case of system (hardware/software) crashes. Furthermore, this research work also
analyzes how queries are decomposed and distributed over geographically separate
nodes and how consistent results be achieved. The experiments have been carried
out on specially designed distributed environment by keeping in mind the future
(efficient) uses of this implementation and its deployment at Quaid-e-Awam
University of Engineering, Science and Technology, Nawabshah and Larkana
campuses which still do not have their own distributed databases. The results are
promising and it is recommended that the distributed databases be implemented at
these campuses as well as at other such environments.

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