Two way communication between arduino and server

there are many help regarding sending data from arduino to server using a GET or POST request.
But in my project I need a two way communication between server and arduino, like some sort of acknowledgement that server has received the data thus arduino doesn't need to resend that particular value.
Also a connection to server from which arduino can receive some values from the server.
Is it possible to look up for a particular value in sever and fetch it in arduino for processing.


in this case you should not use http requests but instead establish a tcp client server connection using sockets.

See this example:

with regards,

Is there any other similar article or reference for two way communication between arduino and database where I can send data to database and receive an acknowledgement from database to arduino.