Table 46describes the details of the Standard Event Subscription ServerFacet. This Facet specifies the standard support for subscribing to events and is intended to supplement any of the FullFeatured Profiles. Support of this Facet requires the implementation of EventTypes representing the Events that the Servercan report and their specific fields. It also requires at least the Server Objectto have the EventNotifier Attributeset. It includes the Servicesto Create, Modify and Delete Subscriptions and to Add, Modify and Remove Monitored Items for Object Nodeswith an “EventNotifier Attribute”. Creating a monitoring item may include a filter that includes SimpleAttribute FilterOperands and a select list of Operators. The operators include: Equals, IsNull, GreaterThan, LessThan, GreaterThanOrEqual, LessThanOrEqual, Like, Not, Between, InList, And, Or, Cast, BitwiseAnd, BitwiseOr and TypeOf. Support of more complex filters is optional. This Facet has been updated to include several optional Base Information ConformanceUnits. These ConformanceUnitsare optional to allow for backward compatibility, in the future these optional ConformanceUnitswill become required, and so it is highly recommended that all servers support them.

Table 46– Standard Event Subscription Server Facet

Group

Conformance Unit / ProfileTitle

Optional

Address Space Model

Address Space Events

False

Base Information

Base Info Device Failure

True

Base Information

Base Info EventQueueOverflow EventType

True

Base Information

Base Info Progress Events

True

Base Information

Base Info SemanticChange

True

Base Information

Base Info System Status

True

Base Information

Base Info System Status Underlying System

True

Monitored Item Services

Monitor Basic

False

Monitored Item Services

Monitor Complex EventFilter

True

Monitored Item Services

Monitor Events

False

Monitored Item Services

Monitor Items 10

False

Monitored Item Services

Monitor QueueSize_ServerMax

False

Subscription Services

SubscriptionBasic

False

Subscription Services

SubscriptionMinimum 02

False

Subscription Services

SubscriptionPublish Discard Policy

False

Subscription Services

SubscriptionPublish Min 05

False