AudioCodes Mediant 4000 SBC, User Manual

Page: 336 / 1037

CHAPTER 17 Quality of Experience
Mediant 4000 SBC | User's Manual
Configuring Clock Synchronization between Device and OVOC
To ensure accurate call quality statistics and analysis by AudioCodes OVOC, you must configure
the device and the OVOC server with the same clock source for clock synchronization. In other
words, you need to configure them with the same NTP server (same address).
The NTP server can be one of the following:
■ OVOC server (also acting as an NTP server)
■ Third-party, external NTP server
To configure, the NTP server's address on the device, see Configuring Automatic Date and Time
using SNTP .
Configuring Firewall Rules for OVOC Traffic
To allow incoming traffic from OVOC, you need to configure the device's firewall (Firewall table)
with additional "Allow" firewall rules, as described in
Configuring Firewall Rules to Allow Incoming
OVOC Traffic on page 142.
Enabling RTCP XR Reporting to OVOC
For the device to be able to send voice metric reports to AudioCodes OVOC, you need to enable
the RTP Control Protocol Extended Reports (RTCP XR) VoIP management protocol. RTCP XR
defines a set of voice metrics that contain information for assessing VoIP call quality and
diagnosing problems. Enabling RTCP XR means that the device can send RTCP XR messages,
containing the call-quality metrics, to OVOC.
For enabling RTCP XR reporting, see Configuring RTCP XR . To configure what to report to OVOC,
see Configuring Quality of Experience Profiles .
Configuring Quality of Experience Profiles
Quality of Experience Profiles enable you to effectively monitor the quality of voice calls traversing
the device in your network. Quality of Experience Profiles define severity thresholds for voice
metrics monitored by the device, which if crossed can result in various actions (discussed later in
the section).
Quality of Experience is configured using two tables with parent-child type relationship. The Quality
of Experience Profile table is the parent, which defines the name of the Quality of Experience
Profile. The Quality of Experience Color Rules table is the child, which defines severity thresholds
per voice metric for the specific Quality of Experience Profile. You can configure up to 256 Quality
of Experience Profiles and up to 256 Quality of Experience Color Rules.
Once configured, you can apply the Quality of Experience Profiles to specific calls (network links),
by assigning them to any of the following configuration entities:
■ IP Groups (see Configuring IP Groups )
■ Media Realms (see Configuring Media Realms )
■ Remote Media Subnets (see Configuring Remote Media Subnets )
The Quality of Experience Profile allows you to configure thresholds for the following monitored
voice metrics:
■ Mean Opinion Score (MOS): MOS is the average grade on a quality scale, expressed as a
single number in the range of 1 to 5, where 1 is the lowest audio quality and 5 the highest audio
quality.
■ Delay (or latency): Time it takes for information to travel from source to destination (round-trip
time).
- 303 -