Two-factor authentication systems rely on a second code, besides the password, to allow access. This code is sent by SMS or is generated by an app and is accessible to only one person, or at least at only one location.
Google has been offering two-factor authentication long since. The first factor is the Gmail password and the second factor a number key which can be known just before the actual login. The usual method this is received in the users registered mobile either by an SMS, a Google voice call that reads out this number or through the Google authenticator application that can be installed in your smartphone. There are a set of backup codes provided to the genuine user in case any of the above are inaccessible. These backup codes are one time use only and are consumed every time one uses them.
I have been using Google two-factor authentication for quite some time and feel that they are convenient enough considering the security they offer. It might be tiresome at times when you have to enter the secondary code but it’s worth the effort as you are sure that no one else can access your account. The second factor is required only while accessing sensitive applications or while accessing the Google account from a device for the first time. It comes with an option for you to allow the device to continue allowing you without requiring the second password for a predetermined time.
The recent attacks on some social networking sites like Facebook and twitter do make us realize how our lives are now tied up with online presence and any hacking could really prove to be disastrous. The hacking of twitter account of Associated Press (AP) which falsely reported twin blasts in the White house and Barack Obama being injured resulted in a sharp decline in stock exchange.
There is lots of banking or credit card applications too that use two factor authentications wherein the second One Time Password (OTP) is generated and sent to the end user on the fly through SMS to the users registered mobile.
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