Send Verification Code to Mobile

Question

Hello all,
I want to send verification code to mobile no while user register himself.I am able to do this i.e send message to user's mobile number,but the main problem is that after entering the verification code by the user ,the page must be redirected to his profile.So my question is that,how the code entered by the user and the code sent to the mobile will be matched,if matched then only redirected to his profile??Totally not getting idea..please help