This Service is used to modify MonitoredItems of a Subscription. Changes to the MonitoredItem settings shall be applied immediately by the Server. They take effect as soon as practical but not later than twice the new revisedSamplingInterval.

The return diagnostic info setting in the request header of the CreateMonitoredItems or the last ModifyMonitoredItems Service is applied to the Monitored Items and is used as the diagnostic information settings when sending Notifications in the Publish response.

Illegal request values for parameters that can be revised do not generate errors. Instead the Server will choose default values and indicate them in the corresponding revised parameter.