14. A method for verifying an identity of at least one user to a text-based communication with at least a second user, comprising: obtaining a plurality of pair-wise characteristic features of at least one prior pair-wise text-based communication between said at least one user and said same second user; comparing the plurality of obtained pair-wise characteristic features to corresponding pair-wise features of a current session of said pair-wise text-based communication between said at least one user and said same second user; and verifying said identity of said at least one user based on a result of said comparison, wherein at least one of said comparing and verifying steps are performed by at least one hardware device.
18. The method of claim 14 , wherein said plurality of pair-wise characteristic features are obtained using machine learning techniques.