Cisco Cisco Prime Unified Operations Manager 8.7 White Paper
Operations Manager Deployment Best Practices
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7.6
Cisco Unified Communications Service Monitor
Integration
A Cisco 1040 Sensor supports up to 50 active calls (100 RTP streams). At an 8-to-1 ratio
(a typical PSTN line-to-user ratio), a Cisco 1040 can monitor approximately 400 phones.
The 8:1 ratio is typically used when provisioning phone lines.
A Service Monitor supports up to ten Cisco 1040s (or about 4000 phones);
An Operations Manager supports up to 10 Service Monitors (or about 40,000 phones).
If there are more than 100 sessions, some of the RTP streams might not be collected
consistently. In this case, since the Cisco 1040 might have missed certain RTP streams,
when the MOS score is calculated, the MOS score is diluted.
Span as close to the phone switch port as possible for the Cisco 1040 to calculate an
accurate MOS.
Configuring the Catalyst Switched Port Analyzer (SPAN) feature:
(a typical PSTN line-to-user ratio), a Cisco 1040 can monitor approximately 400 phones.
The 8:1 ratio is typically used when provisioning phone lines.
A Service Monitor supports up to ten Cisco 1040s (or about 4000 phones);
An Operations Manager supports up to 10 Service Monitors (or about 40,000 phones).
If there are more than 100 sessions, some of the RTP streams might not be collected
consistently. In this case, since the Cisco 1040 might have missed certain RTP streams,
when the MOS score is calculated, the MOS score is diluted.
Span as close to the phone switch port as possible for the Cisco 1040 to calculate an
accurate MOS.
Configuring the Catalyst Switched Port Analyzer (SPAN) feature:
http://www.cisco.com/en/US/products/hw/switches/ps700/products_tech_note09186a008015c612.shtml
Configuring Windows 2000 DHCP Server for Cisco CallManager:
http://www.cisco.com/en/US/products/sw/voicesw/ps556/products_tech_note09186a00800942f4.shtml
Using One DHCP Server for voice and data networks:
http://www.cisco.com/en/US/tech/tk648/tk361/technologies_tech_note09186a0080114aee.shtml
Do not set the Service Monitor MOS threshold to values of 4.3 or greater for a prolonged
period. This will generate a quality of voice trap for every call. The maximum MOS is
4.5.
Usually, one of the reasons why the trap may not get forwarded is because of third party
SNMP tools installed on the OM server. If you have any SNMP tools installed on the OM
server, check to see if the “SNMP Trap Service” under Windows Control Panel ->
Administrative Tools -> Services is running. If it is, stop it and disable it. When the
windows SNMP trap service is running, all traps get redirected to this service and OM
does not get a copy of the trap and hence OM is not able to process the voice quality trap.
period. This will generate a quality of voice trap for every call. The maximum MOS is
4.5.
Usually, one of the reasons why the trap may not get forwarded is because of third party
SNMP tools installed on the OM server. If you have any SNMP tools installed on the OM
server, check to see if the “SNMP Trap Service” under Windows Control Panel ->
Administrative Tools -> Services is running. If it is, stop it and disable it. When the
windows SNMP trap service is running, all traps get redirected to this service and OM
does not get a copy of the trap and hence OM is not able to process the voice quality trap.
7.6.1 Determine a Quality of Voice Baseline for Your Network
In Service Monitor > Setup, enable call metrics archiving. This archives the MOS
parameters for every call. Files are stored in a directory specified during installation.
View the MOS values in these archived files and determine the quality of voice (QoV)
baseline for your network; that is, the typical MOS value that you are experiencing.
Configure the Service Monitor MOS threshold to a value just below your typical value.
The Service Monitor MOS threshold will generate a trap when the MOS value falls
below this number. For example, a very good MOS score is in the low 4 range. If you
typically see a MOS of 4.2 in the archives, then set the MOS threshold to 3.9, for
parameters for every call. Files are stored in a directory specified during installation.
View the MOS values in these archived files and determine the quality of voice (QoV)
baseline for your network; that is, the typical MOS value that you are experiencing.
Configure the Service Monitor MOS threshold to a value just below your typical value.
The Service Monitor MOS threshold will generate a trap when the MOS value falls
below this number. For example, a very good MOS score is in the low 4 range. If you
typically see a MOS of 4.2 in the archives, then set the MOS threshold to 3.9, for