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B.1.2 Server maintains current state only

This example is for Serversthat do not support previous states and therefore do not create and maintain Branchesof a single Condition.

Figure B.1shows an Alarmas it becomes active and then inactive and also the acknowledgement and confirmation cycles. Table B.1lists the values of the state Variables. All Eventsare coming from the same Conditioninstance and therefore have the same ConditionId.

image031.png

Figure B.1– Single state example

Table B.1– Example of a Condition that only keeps the latest state

EventId

BranchId

Active

Acked

Confirmed

Retain

Description

-*)

NULL

False

True

True

False

Initial state of Condition.

1

NULL

True

False

True

True

Alarmgoes active.

2

NULL

True

True

False

True

Conditionacknowledged Confirm required

3

NULL

False

True

False

True

Alarmgoes inactive.

4

NULL

False

True

True

False

Conditionconfirmed

5

NULL

True

False

True

True

Alarmgoes active.

6

NULL

False

False

True

True

Alarmgoes inactive.

7

NULL

False

True

False

True

Conditionacknowledged, Confirm required.

8

NULL

False

True

True

False

Conditionconfirmed.

*) The first row is included to illustrate the initial state of the Condition. This state will not be reported by an Event.

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