This may Usefull for connectivity of SAP Business Objects Data Connectivity (Integration) and many of the times when connectivity for BODI Repositories & Database Connections.
The TNSNAMES.ORA file is where you define your SERVICES. This file usually resides in the $ORACLE_HOME/NETWORK/ADMIN directory.
So We can create our cust defined TNS Service Names based on requirement. Each one holds PORT = 1521
