Calendars are referenced by schedule tables which are defined in the network maintenance facility. Any number of calendars can be defined to the system. Calendars can belong to an owner or be used system-wide. In the calendar maintenance facility, the user can add, delete or update a calendar (system-wide calendars can only be modified by the system administrator).

A calendar is defined by name and year. Defining new calendars or modifying existing ones consists of specifying or marking holidays (non-working days). The non-working days in the example above appear in in red.

Entire Operations accounts for holidays by not activating a network if the scheduled date is marked in the calendar as a holiday.

For detailed information, see the section Calendar Maintenance in the User's Guide.