This Serviceis used to modify MonitoredItemsof a Subscription. Changes to the MonitoredItemsettings 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 CreateMonitoredItemsor the last ModifyMonitoredItems Serviceis applied to the Monitored Itemsand is used as the diagnostic information settings when sending Notifications in the Publishresponse.

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

Table 72defines the parameters for the Service.

Table 72– ModifyMonitoredItems Service Parameters

Name

Type

Description

Request

requestHeader

RequestHeader

Common request parameters (see 7.33for RequestHeaderdefinition).

subscriptionId

IntegerId

The Server-assigned identifier for the Subscriptionused to qualify the monitoredItemId(see 7.19for IntegerIddefinition).

timestampsToReturn

Enum

Timestamps ToReturn

An enumeration that specifies the timestamp Attributesto be transmitted for each MonitoredItemto be modified. The TimestampsToReturnenumeration is defined in 7.40. When monitoring Events, this applies only to Event fields that are of type DataValue.

itemsToModify []

MonitoredItemModifyRequest

The list of MonitoredItemsto modify. This structure is defined in-line with the following indented items.

monitoredItemId

IntegerId

Server-assigned id for the MonitoredItem.

requestedParameters

Monitoring Parameters

The requested values for the monitoring parameters. The MonitoringParameterstype is defined in 7.21.

If the number of notifications in the queue exceeds the new queue size, the notifications exceeding the size shall be discarded following the configured discard policy.

Response

responseHeader

Response Header

Common response parameters (see 7.34for ResponseHeaderdefinition).

results []

MonitoredItemModifyResult

List of results for the MonitoredItemsto modify. The size and order of the list matches the size and order of the itemsToModifyrequest parameter. This structure is defined in-line with the following indented items.

statusCode

StatusCode

StatusCodefor the MonitoredItemto be modified (see 7.39for StatusCodedefinition).

revisedSampling

Interval

Duration

The actual sampling interval that the Serverwill use. The Serverreturns the value it will actually use for the sampling interval. This value is based on a number of factors, including capabilities of the underlying system.

The Servershall always return a revisedSamplingIntervalthat is equal or higher than the requestedsamplingInterval. If the requestedsamplingIntervalis higher than the maximum sampling interval supported by the Server, the maximum sampling interval is returned.

revisedQueueSize

Counter

The actual queue size that the Serverwill use.

filterResult

Extensible Parameter

MonitoringFilter Result

Contains any revised parameter values or error results associated with the MonitoringFilter specified in the request. This parameter may be null if no errors occurred. The MonitoringFilterResultparameter type is an extensible parameter type specified in 7.22.

diagnosticInfos []

DiagnosticInfo

List of diagnostic information for the MonitoredItemsto modify (see 7.12for DiagnosticInfo definition). The size and order of the list matches the size and order of the itemsToModifyrequest parameter. This list is empty if diagnostics information was not requested in the request header or if no diagnostic information was encountered in processing of the request.

Table 73defines the Serviceresults specific to this Service. Common StatusCodesare defined in Table 182.

Table 73– ModifyMonitoredItems Service Result Codes

Symbolic Id

Description

Bad_NothingToDo

See Table 182for the description of this result code.

Bad_TooManyOperations

See Table 182for the description of this result code.

Bad_TimestampsToReturnInvalid

See Table 182for the description of this result code.

Bad_SubscriptionIdInvalid

See Table 182for the description of this result code.

Table 74defines values for the operation level statusCodeparameter that are specific to this Service. Common StatusCodesare defined in Table 183.

Table 74– ModifyMonitoredItems Operation Level Result Codes

Symbolic Id

Description

Bad_MonitoredItemIdInvalid

See Table 183for the description of this result code.

Bad_MonitoredItemFilterInvalid

See Table 183for the description of this result code.

Bad_MonitoredItemFilterUnsupported

See Table 183for the description of this result code.

Bad_FilterNotAllowed

See Table 182for the description of this result code.