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B.1.2 Server maintains current state only

This example is for Servers that do not support previous states and therefore do not create and maintain Branches of a single Condition.

Figure B.1 shows an Alarm as it becomes active and then inactive and also the acknowledgement and confirmation cycles. Table B.1 lists the values of the state Variables. All Events are coming from the same Condition instance and therefore have the same ConditionId.

image036.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

Alarm goes active.

2

NULL

True

True

False

True

Condition acknowledged Confirm required

3

NULL

False

True

False

True

Alarm goes inactive.

4

NULL

False

True

True

False

Condition confirmed

5

NULL

True

False

True

True

Alarm goes active.

6

NULL

False

False

True

True

Alarm goes inactive.

7

NULL

False

True

False

True

Condition acknowledged, Confirm required.

8

NULL

False

True

True

False

Condition confirmed.

*) 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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