調校一個DBLINK 連線時間太久

由於我方(政府機關機房)的DB 要連線去 另一個政府機關的ORACLE DB 去作DBLINK, 可是反映說連線動作時間太久,  經過思索一番認為是FW及IPS  檢查封包時間太久(是可以過)
due to a dataflow change , origin they sync data  to 2 Database from local government  to two Bureau under Ministry of Economic Affair. one of  database local on in my office . another one is main database on
other government  machines farm. now is change 3 tier layout just keep one database . our database is canceling soon. we need create a dblink  to their db. but when we test . to slow .
so I think it will be TCP/IP head check  spend many time.
原本(ORIGIN Response  time ) need : 16 MINS .
after  addition IP and port to white list on FW.  it from 16 mins to 13 Mins.then
I ask soc to add 2 ip on 2 IPS . it from 13 mins to 7mins .
still to slow .