  Data replication is a common method used to improve the performance of data
access in distributed database systems. In this paper, we present an object
replication algorithm in distributed database systems (ORAD). We optimize the
created replicated data in distributed database systems by using activity
functions of previous algorithms, changing them with new technical ways and
applying ORAD algorithm for making decisions. We propose ORAD algorithm with
using effective factors and observe its results in several valid situations.
Our objective is to propose an optimum method that replies read and write
requests with less cost in distributed database systems. Finally, we implement
ORAD and ADRW algorithms in a PC based network system and demonstrate that ORAD
algorithm is superior to ADRW algorithm in the field of average request
servicing cost.
