User's Manual

AR 400 Reader User’s Manual  2003-2004 Matrics, Inc. 37
This event should be processed in a timely fashion to give meaningful results, so set the Notify
option to Immediate (the default for this event type.)
Threshold Events
A Threshold Event is generated when the number of visible tags drops below or rises above a threshold
that you specify via a Tag List notification reply. Before you can generate Thresholds Events, you must
import and associate rules for your thresholds. Since some users may not want to set up rules and
thresholds, by default, this event’s notify option is set to Never. Threshold events are only generated
when the notify option is enabled, and User IDs and thresholds have been supplied via a Tag List. Since
there may be cases, in the normal course of operation, that a tag may have transient periods when it is
changing visibility in the system, set the Notify option to Moderated to smooth out temporary conditions,
and generate an event only when the tag is not experiencing a temporary moment of invisibility.
Network Status Events
Network Status Events alert you to changes in status of the managed resources of the Reader. For
example, if a Reader problem is detected, an event is generated by the Reader and sent without a server
request.
If you want to receive Network Status Event notifications, you must subscribe to them by setting the
SNMP configuration on the Event Notifications page. If the SNMP host is not set (or is not valid), no
Network Status Events will be sent
Network Status Events are divided into two categories, ‘device’ and ‘program.’ A Device Event notes the
change in a device’s status. A Device Event is further divided into two categories, ‘user’ and ‘system.’
Both categories have an addition specification as to whether the status change is being reported for itself
or in association with a ‘parent’ device.
For example, if the ‘user’ disabled a Reader, several events would be generated. The Reader would get a
‘user/disable’ status notification. The Read Point(s) below the Reader would get a ‘user/disable/parent’
notification. If the system detected a problem with the Reader, it would automatically disable the device,
and the matching events would be generated. These classifications allow you to not only see the overall
effect on the Reader Network, but also allow the likely offending component to be identified. When the
fault is fixed, you can ‘enable’ the device. Any device below it that was ‘parent disabled’ is automatically
brought back online.
Exception Events
Exception Events provide the same type of information available via SNMP, except over XML. An
Exception Event gives you information when a device goes off-line, polling is turned off, etc.. You may
choose this option if you don’t support SNMP, but still want to receive feedback if the device/program
changes state. XML is enabled by setting the Notify option for Exception Events to ‘Immediate’ in the
Notify column on the Event Notifications page.