Digipass Plug-In for IAS Product Guide - Vasco

Digipass Plug-In for IAS Product Guide Digipass
Time-based
A time-based Application will change the OTP to be displayed based on the current time. The
common time step used is 36 seconds – and means that the OTP to be displayed will change
every 36 seconds, whether or not an OTP has been requested from the Digipass.
Event-based
An event-based Digipass Application will display a new OTP each time a request for an OTP is
made.
Challenge/Response
Challenge/Response Digipass Applications can be either time-based or non-time-based:
Time-based
A time-based Challenge/Response Digipass Application will generate an OTP based on the
Challenge given and the current time. The common time step used is 9 hours ('slow
challenge'). This would mean that if the exact same Challenge were given to a Digipass within
a 9 hour period, the Digipass Application will generate the same OTP. However, Challenges
are very rarely repeated within such a time period.
Non-time-based
A non-time-based Challenge/Response Digipass Application will generate an OTP based only on
the Challenge given.
2.2.3.3 OTP Length
The length of the OTP (excluding check digit) generated by the Digipass for Response Only
and Challenge/Response Digipass Applications.
Check Digit
A check digit may be added to each OTP. This is generated from the response and allows for
faster invalidation of incorrect OTPs.
2.2.3.4 Challenge Length
The length of the Challenge (excluding check digit) which should be expected by the Digipass.
This is used by the Challenge/Response Digipass Application.
Check Digit
A check digit may be expected with each Challenge. This is generated by the server from the
Challenge and allows the Digipass to reject most invalid Challenges.
© 2005 VASCO Data Security Inc. 26