1) Acknowledgement 2) Acknowledgment 3) Handclasp 4) Handshake 5) Shake 1) Handclasp 2) Handshake 
In information technology, telecommunications, and related fields, handshaking is an automated process of negotiation that dynamically sets parameters of a communications channel established between two entities before normal communication over the channel begins. It follows the physical establishment of the channel and precedes normal information...
A protocol that is used to communicate between devices, using extra controls (RTS/CTS system) or special characters (XON/XOFF).
In computing, handshaking refers to hardware or software activity designed to start or keep two machines or programs in synchronisation as they do protocol.
Exchange of predetermined codes and signals between two data devices to establish and control a connection
The initial exchange between two communications systems prior to and during transmission to ensure proper data transfer.