This article provides two sample calculations for dynamic time windows.
Example 1
Initial parameters
Authenticator application time step: 36 seconds
Authenticator application usage: Authentication (Password validation)
Identification time window: 10 Digipass time steps
Synchronization time window: 6 hours = 21600 seconds
DTWAT
DTWAT= ((Time step * (ITimeWindow -1)) / 8) = ((36 * (10-1)) / 8) = 40.5 days
First authentication
A new user has not yet successfully authenticated:
| Used time window | = max (SyncWindow, ITimeWindow * time step) |
| = max (21600 seconds, 360 seconds) = 21600 seconds = 600 time steps | |
| = +/- 300 time steps |
Authentication before DTWAT
The user authenticates within 40.5 days after the last successful verification:
| Used time window | = ITimeWindow * time step |
| = 10 time steps * 36 seconds | |
| = 360 seconds | |
| = +/- 5 time steps |
Authentication after DTWAT
The user authenticates between 40.5 days and 2695.5 days after the last successful verification.
| Used time window | = Time step + (Days lapsed * 8) |
| 40.5 Days Lapsed | 99 Days Lapsed | 365 Days Lapsed | 2695.5 Days Lapsed | |
|---|---|---|---|---|
| Used time window calculation | 36 + (40.5 * 8) | 36 + (99 * 8) | 36 + (365 * 8) | 36 + (2695.5 * 8) |
| Used time window (seconds) | 360 s | 828 s | 2956 s | 21600 s |
| Used time window (time steps) | 10 | 23 | 82 | 600 |
Example 2
Initial parameters
Authenticator application time step: 8 seconds
Authenticator application usage: Authentication (password validation)
Identification time window: 2 Digipass time steps
Synchronization time window: 1 hour= 3600 seconds
DTWAT
DTWAT= ((Time step * (ITimeWindow -1)) / 8) = ((8 * (2-1)) / 8) = 1 day
First authentication
A new user has not yet successfully authenticated:
| Used time window | = max (SyncWindow, ITimeWindow * time step) |
| = max (3600 seconds, 16 seconds) | |
| = 3600 seconds = 450 time steps = +/- 225 time steps |
Authentication before DTWAT
The user authenticates within 1 day after the last successful verification:
| Used time window | = ITimeWindow * time step |
| = 2 time steps * 8 seconds | |
| = 16 seconds = 2 time steps = +/- 1 time step |
Authentication after DTWAT
The user authenticates between 1 day and 449 days after the last successful verification:
| Time window | = Time step + (Days lapsed * 8) |
| 1 Day Lapsed | 7 Days Lapsed | 365 Days Lapsed | 449 Days Lapsed | |
|---|---|---|---|---|
| Used time window calculation | 8 + (1 * 8) | 8 + (7 * 8) | 8 + (365 * 8) | 8 + (449 * 8) |
| Used time window (seconds) | 16 s | 64 s | 2928 s | 3600 s |
| Used time window (time steps) | 2 TS | 8 TS | 366 TS | 450 TS |