Oracle databases are often shared across geographical areas, so it's imperative that the Oracle professional understand how database performance is affected by network communications. The Transparent Network Substrate (TNS), provided by Oracle, allows distributed communications between databases.
The TNS, which is a distributed protocol, allows for transparent database communications between remote systems. The TNS serves as an insulator between Oracle's logical data request and the physical communications between the remote servers. As such, the network administrator is able to control much of the network performance tuning. The Oracle administrator, then, has little control over the network settings that can affect overall database performance.
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