Last week received the following email message from a Hong Kong service provider:
|"Is there a product that actively monitors call performance in a Cisco Unified Communications environment?"|
|Recommended that the Hong Kong service provider investigate and Download the Free Cisco Unified Service Monitor 2.0 Evaluation Kit.
The free Cisco Unified Service Monitor 2.0 - CUSM 2.0 evaluation software provides users with a free 90-day evaluation period.
The following is a brief overview:
Cisco Unified Service Monitor is an application in the Cisco Unified Communications Management Suite used to monitor quality of voice in real time. The Cisco Unified Service Monitor analyzes and reports on voice quality using Mean Opinion Scores (MOS) received from Cisco Unified CallManager clusters and Cisco 1040 Sensors.
This solution helps enable IP network and IP telephony managers to more effectively manage their IP communications infrastructure by providing near real-time quality of voice metrics and providing alerts when the voice quality falls below a user-defined threshold.
The solution consists of these components:
|Cisco 1040 Sensor - A hardware appliance or probe used to monitor quality of voice for up to 100 active RTP streams per minutes. The sensor then forwards a quality of voice metric in the form of a Mean Opinion Score (MOS) for each monitored stream every 60 seconds to the Cisco Service Monitor server.|
Cisco 1040 Sensor
|Cisco Unified CallManager - Stores the CVTQ data from gateways and phones in Call Detail Records (CDRs) and Call Management Records (CMRs), which is then sent or retrieved by Service Monitor.|
|Cisco Service Monitor Server - Compares the quality of voice metrics incoming from the Cisco 1040s to a user-defined threshold. If a threshold violation is detected, Cisco Service Monitor will forward a SNMP trap containing the pertinent information to as many as four trap recipients. Cisco Service Monitor can also optionally archive all incoming call metrics, and is used to manage the Cisco 1040 sensors.|
|One of the functions of the SM server is to manage the Cisco 1040 sensors. This entails creating the configurations for the sensors which informs the sensor where to forward the quality of voice metrics. These configurations (as well as the Cisco 1040 binary image) must then be manually copied from the SM server to a TFTP server. The reason for this is the Cisco 1040 operates similar to an IP Phone - when it is first booted up it receives not only its IP address from a DHCP server, but also the IP address of a TFTP server (DHCP option 150) where it can find its binary image and configuration.|
|The sensors have two Ethernet interfaces: one to report the call metrics to the SM server, and the other is connected to the SPAN port of a switch used to continuously monitor active calls. This means that the administrator needs to SPAN the appropriate ports or VLAN to a SPAN port on the connecting switch. The sensor also receives its power from switch ports that support Power over Ethernet (PoE). The sensors monitor each call stream for 60 seconds and then forwards the metrics to the SM server in the form of a Syslog message.|
|In addition, a MOS value for an entire call is calculated on some gateways and IP phones using the Cisco Voice Transmission Quality (CVTQ) algorithm. At the termination of a call, Cisco Unified CallManager stores the CVTQ data in Call Detail Records (CDRs) and Call Management Records (CMRs).|
|The SM server retrieves the MOS values from the Cisco 1040s and the Cisco Unified CallManagers and compares the MOS metric against the user define threshold. Any threshold violation is then forwarded as an SNMP trap to up to four trap receivers. Typically, one of those receivers is Cisco Operations Manager which then displays the trap on its Service Quality Alerts dashboard.|
|Access to both Cisco Operations Manager and Cisco Service Monitor is via a standard web-browser.|
|The Cisco 1040 sensors use an algorithm specifically created for determining voice quality in a data network – G.107 R factor. Among other things, this algorithm takes into account delays and equipment impairment factors, and creates a score between 0 and 100 (poor to excellent).|
|Since the MOS is still the most widely used metric for call quality, the sensor converts the R factor into a MOS value and transmits this to the SM server.|
|A similar algorithm is used for the CVTQ values. In the end, both the Cisco 1040 sensors and Cisco Unified CallManagers report MOS to the Cisco Service Monitor application.|
|For larger enterprises (generally more than 5,000 phones), it is possible to have Cisco Operations Manager and Cisco Service Monitor co-reside on the same platform depending on the number of calls to be monitored, but a separate platform is recommended.|
|Depending on the number of calls to be monitored, multiple instances of SM can be deployed and still all report to a single instance of Cisco Operations Manager or other trap receiver.|
|Each dedicated SM server can support up to 50 Cisco 1040 Sensors to provide a distributed, highly scalable, and redundant mechanism to analyze IP telephony voice quality.|
|A separate SM is not required at each remote branch location.|
|The sensors’ configuration file specifies the location of the primary and secondary SM servers.|
Brad Reese cofounded BradReese.Com Cisco Refurbished, which enables affordable Cisco networks globally by assuring customer satisfaction with guaranteed one year warranties on both Cisco Repair as well as Refurbished Cisco.
Don't be shy, contact Brad Reese online or call him at 717-707-0704.