title: How to distinguish between Known IP and unknown IP
body: <p>i need to develop a web application that can identify a known machine and unknown by storing a pair(sourceIP,valid username) at server side for which previous login was successful.when anyone login from unknown machine how can be identified.web app is hosted in local host.is it possible to get the client ip.when retrieving client IP i get only 127.0.0.1 which is localhost.anyone having any idea...? </p>