Cross-system sharing

To ensure that users have access to current data, VLF needs to be notified when changes are made to data that is shared across systems. For instance, if a user changes shared data but VLF on all the affected systems is not notified, VLF users on those systems would not have access to current data.

Under certain circumstances, VLF is automatically notified of changes to data it manages. At other times, someone, such as a user or an application programmer, needs to notify VLF that data has been changed. Table 1 summarizes when notification to VLF is automatic. A more detailed explanation follows the figure.