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* Description: Knowledge of Oracle client initating session with remote listener
* Compatiablity: RDBMS 11g, 12c
* Date: 05:04 PM EST, 04/23/2017
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<1> Client/Listener connection initating process:
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     |__ a) Client on remote server side sends over an NSPTCN packet to get connect with listener .......................... [ client ----- request ------> listener       ]
         b) Listener will ask database to initiate a dedicated database process to receive the connection ..  .............. [ listener --- request ------> Server process ]
         c) After the dedicate database process started, the listener will hand over the connection request from client to the database process.
         d) The server process will take over the connection from the listener to continue the handshake with the client.
            Listener likes "an agent" in the middle bridge them together ................................................... [ client-----exchange info directly with---->DB process ]
         e) Server process and client exchange information required for establishing a session, such as log on authentication info.
         f) Finally, we can call it "a session got established".
		 
		 
<2> Reference:
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     |__ https://docs.oracle.com/cd/B12037_01/network.101/b10775/concepts.htm#i1045403