dropbox sign in with google authenticator not working

One-time password generated based on time can be done following the same principles as the above, except for the automatic definition of time intervals based on counter. The code's next part leads to extraction of binary value of an integer of 4 bytes and then it is shrunk to the required number of digits. Hashing method can be used for that and this hash has to be computed for the counter's current value. With every authentication success iteration number will be incremented on server and client. For the generation iteration number has to be converted to byte. Generation of one-time passwords requires three types of information- counter number, the output's number of digits which are limited to 6 as well as the secret key. After agreeing on the secret key, the application generates a 6 digit key which will be the sole data which will be passing between the server and client, without the data passing through servers of Google.

The very same algorithm as well as secret key is then used by the server for the checking of the code. Then any of the algorithms are used by Authenticator and a code is generated for the entering during the process. This key can be typed by the user in Google Authenticator or QR code can be used for the automatic setting up of the application. The user and the server have to agree on some secret key that will be used as seed value for hashing function. Now Google Authenticator works by implementing algorithms defined in RFC 6238 which is time-based implementation of the authentication process and RFC 4226 which is counter-based one. A 6 digit counter or time based number is provided by it which acts as 2nd factor for the authentication. This is available on Blackberry, iOS and Android operating systems. The software based Google Authenticator is an authentication token based on two factors as is apparent from the name itself. This helps in mitigating chances of attackers intercepting the web traffic. For example the code of RSA keys is changed every minute while it is changed by Google Authenticator every 30 seconds. Factors like mobiles or RSA keys are best and most common sources used for the generation of one time passwords which is changed over time. In two factor authentication you have to use a combination of at least two factors.

Dropbox sign in with google authenticator not working