Who has started the option of Google’s 2-step verification & Facebook’s Login Approval knows that the sms containing verification code of Google delivers instantly but Facebook’s Security code delivers too late (for max 12 hours) at least for 5 to 6 days in a month. If you contact with Telecom company, they will say “Facebook did not pass that to our server” AND if you contact with Facebook, they will say “We have already sent the code to Telecom’s server”. Google has two alternative methods: If sms delivery fails, anyone can collect code by receiving phone call. Beside that they provide Ten “One Time Use – Backup Code”. If Facebook starts these two alternatives like Google then we can log in to Facebook easily.
Yahoo uses different method “Sign in with Google” through which, based on “One Google Account : One Yahoo Account” policy anyone can login to Yahoo’s website without password just by clicking on “Sign in with Google”. If Twitter, GoDaddy, Paypal, LinkedIn, Odesk, Wikipedia, Everyone, Alexa provide this opportunity then we will be safe from Hacker or Key Logger software.
Tawhidur Rahman Dear's Blog, Articles and Stories 