Table 38describes the details of the Standard DataChange Subscription ServerFacet. This Facet specifies the standard support of subscribing to data changes. This Facet extends features and limits defined by the Embedded Data Change SubscriptionFacet. As a minimum, Serversshall support 2 Subscriptions with at least 100 items for at least half of the required Sessions. The 100 items shall be supported for at least half of the required Subscriptions. Queuing with up to two queued entries is required. Support of five parallel Publish requests per Sessionis required. This Facet also requires the support of the triggering service. This Facet has been updated to include optional ConformanceUnitsto allow for backward compatibility. These optional ConformanceUnitsare highly recommended, in that in a future release they will be made mandatory.

Table 38– Standard DataChange Subscription Server Facet

Group	Conformance Unit / ProfileTitle	Optional
Profile	Embedded DataChange Subscription ServerFacet	False
Base Information	Base Info GetMonitoredItems Method	True
Method Services	MethodCall	True
Monitored Item Services	Monitor Items 10	False
Monitored Item Services	Monitor Items 100	False
Monitored Item Services	Monitor MinQueueSize_02	False
Monitored Item Services	Monitor Triggering	False
Monitored Item Services	Monitored Items Deadband Filter	False
Subscription Services	SubscriptionMinimum 02	False
Subscription Services	SubscriptionPublish Min 05	False