Ephemeral Ports

When a client initiates a communication with server at well known port,  you only know about the server port like for SFTP port 22 or HTTP port 80 but which port is used for communication on client side..you don't have any idea. This is called ephemeral port. Depending upon the client device/OS , it is picked up from a range of ports , used during the communication and released after that. 

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