An apparatus, method, and computer program for securely sending a network one-time-password (OTP) from a user computer to an authentication server. A Network Client Application in the user computer interfaces with the authentication server, and a Mobile Server Application in the user computer interfaces with a Mobile Client Application in a mobile computing device (MCD) such as a smartphone. When a user enters a User ID and password into the user computer, the Network Client Application sends the User ID to the authentication server to obtain an index value (Index-1) from the authentication server. The Mobile Server Application authenticates the MCD and then sends Index-1 to the MCD to obtain a network OTP second factor from the MCD. The Network Client Application modifies the user password in accordance with the network OTP second factor to create the network OTP, and sends the network OTP to the authentication server.