Time budget in SVCN - System description SVCN

The access authorisations are stored on the card. For this reason, a time budget or an expiry date is set for the cards after which they become invalid. Users must therefore regularly hold their cards to the updaters in order to renew their time budgets. Frequent contact between cards and updaters effectively connects the virtual network to the integrator system. Through this connection, real status (locking system) and planned status (software) remain synchronous, including:

Changes to authorisations
Information about lost cards
Card-specific access lists
Status of locking devices

The time budget or expiry date is essential for most cards in the system. However, it must also be possible to create some cards that are excluded from this:

Different general cards (time budget depending on customer)
Emergency access or fire service cards
Cards with special functions (switchover cards, blacklist cards, etc.)

For card types, see also Card Types (SVCN).

Time budgets should always be used in offline systems. Otherwise, the cards are rarely or never held to the updaters and the connection of the virtual network to the integrator system is poor. This leads to different statuses in the software and locking system in the long term.

Recommended time budgets

This table is a guide to determine a suitable length for the time budget of the cards. Other soft factors should also be taken into account:

Updater installation situation: Update terminal or door opener
Building structure (cards use the updater unconsciously and automatically)
Type of end customer (different operating times, e.g. schools and hospitals)

Different user groups can be assigned different time budgets.

Time budget	Note
≤ 8 hours	Very safe Information about lost cards not necessary (depending on customer) Public holiday list possible Implausible for the end user (time budget can expire during working hours)
8 hours to 24 hours	Very safe Information about lost cards not necessary (depending on customer) Public holiday list possible Practical for most end users
24 hours to 168 hours	Very safe to sufficiently safe Information about lost cards Blacklist card recommended (manual blacklist update: Securing critical doors, e.g. in the building envelope) Public holiday list possible Implausible for the end user (time budget top-up at updater is often forgotten)
≥ 168 hours	Unsafe (Lost cards can be found and then used for a long time) Information about lost cards recommended (but cards rarely on the updater, therefore information may be transferred slowly in the virtual network) Blacklist card strongly recommended (manual blacklist update: Securing critical doors, e.g. in the building envelope) Public holiday list not possible Implausible for the end user (time budget top-up at updater is often forgotten)

NOTE

Security risk due to lost cards

Lost cards can be found by unauthorized persons. These can then open locking devices until the blacklist in the locking devices has been extended with the lost card.

Use reasonable time budgets to always synchronize the system promptly.
Don't choose unnecessarily long time budgets. Cards whose time budget has expired and which are blocked in the system will normally no longer receive an extension from the integrator's updater.