When your client will login from browser he will get a PIN code via SMS, and browser will required that PIN code if client enter PIN code correctly access will be granted. and browser will ask that you want to remember this browser or not?. If client click remember then system will remember that browser and will not required SMS authentication again.
For example any hackers or any other person find your password via any illegal way. And try to login System will send a PIN code to real account owner and without PIN code access will not be granted and an alert will be transmitted to account owner.
So Now a days Two step authentication is very very important. because every one need strong security and clients also need their accounts secure from bad hands.
Hajana One has a solution for those who want to secure their client's accounts via two step authentication. We have an affordable price for this service. We can setup two step authentication on your website or any other project.