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Enabling V-Clock for Sentinel HL (Driverless Configuration) Keys

This section is relevant only for LDK Products/Entitlements.

V-Clock is a virtual clock that is available in Sentinel SL keys and in all types of Sentinel HL (Driverless configuration) keys except for Sentinel HL Basic keys.

• For Products that are licensed with Sentinel HL (Driverless configuration) keys, V-Clock must be specifically enabled for each Product.
• For Products that are licensed with Sentinel SL keys, V-Clock is always available.

V-Clock does not provide the same level of control as the real-time clock in Sentinel HL Time keys and Sentinel HL NetTime keys. However, V-Clock prevents the end user from using a protected application beyond expiration date by setting the system time back to an earlier date and time.

The expiration period or date for a time-based license is initially calculated according to the system clock of the end user's machine. Sentinel License Manager reads the system time at Sentinel License Manager startup (by default, part of the machine startup). Sentinel License Manager subsequently uses its internal running time to calculate the time. When an application that is protected with V-Clock is executed for the first time, Sentinel License Manager queries its internal clock to determine the start time of the software’s license duration.

• If the license duration is a fixed period (for example, 30 days or 1 year), Sentinel License Manager calculates the actual date on which the license must stop working and the information is stored in the secure storage area of the protection key. The secure storage for a Sentinel SL key is on the hard drive of the end user's computer. The secure storage for a Sentinel HL key is in the HL key.
• If the license is to expire on a specific date, Sentinel License Manager records that date. Expiration time is determined using the formula:

  [current Sentinel License Manager time] + [number of seconds to expiration]

  The information is stored in the secure storage area of the protection key.

For more information, see How Sentinel LDK Protects Time-based Licenses With V-Clock.