Белая книга для Cisco Cisco Prime Unified Service Monitor 8.7
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© 2007 Cisco Systems, Inc. All rights reserved. This document is Cisco Public Information.
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It is imperative to have a rock-solid network infrastructure. The network infrastructure offers the
platform for advanced technologies such as voice, video, wireless, and so on.
platform for advanced technologies such as voice, video, wireless, and so on.
Cisco Unified Service Monitor
Given the dynamic nature of IP networks and the strong dependency of the Cisco Unified solution
on network infrastructure, it is imperative for network administrators to have voice quality information on
real calls (not simulated calls) at their fingertips to help enable them to resolve voice quality
problems. Cisco Unified Service Monitor meets user requirements in reporting voice quality issues.
on network infrastructure, it is imperative for network administrators to have voice quality information on
real calls (not simulated calls) at their fingertips to help enable them to resolve voice quality
problems. Cisco Unified Service Monitor meets user requirements in reporting voice quality issues.
There are two ways to measure call quality using Service Monitor:
●
Call quality measurement and reporting as the call progresses: Use the Cisco 1040 Sensor
hardware.
hardware.
●
Call quality measurement and reporting at the end of the call: Use the Cisco Unified
Communications Manager Cluster (4.2.x and 5.x and above provide Cisco Voice
Transmission Quality–based mean opinion scores [MOSs]; for earlier call manager versions,
Service Monitor reports jitter and packet loss for the call).
Communications Manager Cluster (4.2.x and 5.x and above provide Cisco Voice
Transmission Quality–based mean opinion scores [MOSs]; for earlier call manager versions,
Service Monitor reports jitter and packet loss for the call).
Service Monitor analyzes the data that it receives and sends traps when a MOS falls below a
threshold. Service Monitor provides a set of default global thresholds, one per supported codec. It
helps enable you to change the default global thresholds and to override them by creating sensor
threshold groups and cluster threshold groups.
threshold. Service Monitor provides a set of default global thresholds, one per supported codec. It
helps enable you to change the default global thresholds and to override them by creating sensor
threshold groups and cluster threshold groups.
Data Collection and Analysis
Service Monitor receives and analyzes MOSs from the following sources when they are installed
and configured properly in your voice network:
and configured properly in your voice network:
●
Sensors:
Cisco 1040 Sensors compute MOSs for each Real-Time Transport Protocol
(RTP) stream and send syslog messages to Service Monitor every 60 seconds.
●
Cisco Voice Transmission Quality:
Cisco Unified Communications Manager collects data
from Cisco H323 Voice Gateways and Cisco IP phones; MOSs are calculated on the
gateways and phones using the Cisco Voice Transmission Quality algorithm. At the
termination of a call, Cisco Unified Communications Manager stores the data in call detail
records (CDRs) and call management records (CMRs).
gateways and phones using the Cisco Voice Transmission Quality algorithm. At the
termination of a call, Cisco Unified Communications Manager stores the data in call detail
records (CDRs) and call management records (CMRs).
The Cisco Unified Service Monitor 2.0 software runs on an Intel-based machine, with a server
running Windows 2003 with Service Pack 1. The software must be procured by the customers.
running Windows 2003 with Service Pack 1. The software must be procured by the customers.
Cisco 1040 Sensor-Based Call Quality—R-Factor:
The ITU E model, as defined in G.107 (03/2003), predicts the subjective quality that is experienced
by an average listener by combining the impairment caused by transmission parameters (such as
loss and delay) into a single rating: the transmission rating factor R (the R-factor). This rating,
expressed on a scale of 0 (worst) to 100 (best) can be used to predict subjective user reactions,
such as the MOS. The MOS can be obtained from the R-factor with a converting formula. Thus the
R rating is an estimate of the quality that can be expected if the network is realized the way it is planned.
by an average listener by combining the impairment caused by transmission parameters (such as
loss and delay) into a single rating: the transmission rating factor R (the R-factor). This rating,
expressed on a scale of 0 (worst) to 100 (best) can be used to predict subjective user reactions,
such as the MOS. The MOS can be obtained from the R-factor with a converting formula. Thus the
R rating is an estimate of the quality that can be expected if the network is realized the way it is planned.
Cisco 1040 Sensor Deployment
The Cisco 1040 Sensor is the hardware component that will be deployed on the Switched Port
Analyzer (SPAN) port of a switch, as close to the IP phones and other problem areas (gateways,
and so on) as possible,
The Cisco 1040 Sensor is the hardware component that will be deployed on the Switched Port
Analyzer (SPAN) port of a switch, as close to the IP phones and other problem areas (gateways,
and so on) as possible,