Embodiments of the invention enable {HEAD ~ cardholders} conducting {TAIL ~ an online transaction} to be authenticated in real time using a challenge response application 
conducting
Embodiments of the invention enable { HEAD ~ cardholders } conducting { TAIL ~ an online transaction } to be authenticated in real time using a challenge response application
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH