Chapter 11 Quality Monitoring and Statistics Gathering

H.248 Network Package Quality Alert Event and Middlebox Pinhole Timer Expired Event

H.248 Network Package Quality Alert Event and Middlebox Pinhole Timer Expired Event

When the DBE detects media loss (media has stopped flowing and a call is not on hold), the DBE may issue one or more H.248/Megaco events to the media gateway controller (MGC): a Network (nt) package Quality Alert (qualert) event, a Middlebox Pinhole Timer Expired event1, or both events.

Network Package Quality Alert Event

The DBE will return a Network (nt) package Quality Alert (qualert) event when media loss is detected if the media gateway controller (MGC) requests it.

When the MGC requests an nt/qualert event, it specifies a Threshold parameter value based on a percentage of network quality loss. Although the DBE accepts any valid value (0 through 99) for this parameter, only a value of 99 triggers the generation of the nt/qualert event because the DBE only detects complete media failure and is not able to detect partial frame loss, which can occur during network congestion.

Requests for nt/qualert events are on a per-stream or per-termination basis, but the event is always reported on a per-stream basis. The event subscription can be added or removed during the lifetime of the stream. The event is monitored independently for each side of the stream.

Middlebox Pinhole Timer Expired Event

The h248-media-alert-eventcommand defines whether a Middlebox Pinhole Timer Expired event is generated when the DBE detects media loss.

Note The Middlebox Pinhole Timer Expired event and the Network package Quality Alert event are independently generated, so that either, both, or neither of these events are generated when the DBE detects media loss.

DBE Restrictions

The following are restrictions of DBE support for the H.248 Network Package Quality Alert Event feature:

The DBE does not send notification when the last termination in a context expires.

The DBE deletes the context when all of its terminations time out during an H.248 association outage.

When an H.248 association is down and then resumes, the DBE resumes sending notification events. However, during the H.248 association outage, notification events may be lost after retries.

1. ETSI TS 101 332 Version 4.1.1

Cisco IOS XE Integrated Session Border Controller Configuration Guide for the Cisco ASR 1000 Series Aggregation Services Routers

 

OL-15421-01

11-5

 

 

 

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Cisco Systems ASR 1000 manual Network Package Quality Alert Event, Middlebox Pinhole Timer Expired Event, 11-5