Cisco IP SLA monitoring

Monitor VoIP using Cisco IP SLA and NetFlow

VoIP(Voice over Internet Protocol) is a general term for a family of transmission technologies for delivery of voice communications over IP networks such as the Internet or other packet-switched networks.

Most of the businesses are gradually migrating to VoIP technology because of its bandwidth efficiency and low cost. All communications(phone calls, faxes, voice mail, e-mail, Web conferences and more) can be treated as discrete units. VoIP runs both voice and data communications over a single network, which can significantly reduce infrastructure costs.

In VoIP based voice communication, the analog voice signal is converted to the digital format which in turn is converted into internet protocol(IP) packets. These IP packets are transmitted over the internet. The above process is exactly reversed at the receiving end.

The greatest concern for any business using VoIP for their voice communications is quality. Jitter, latency and packet loss cause a drop in the quality of the voice communication being transmitted. Hence we need to monitor VoIP to maintain the quality of the voice communications by making sure the jitter, latency and packet loss values do not exceed the threshold.

Top call path dashboard

Top Call Path Dashboard:

The top call path widgets shows the locations and their destinations along with the jitter, latency and packet loss details. It lists the bad call paths details on your VoIP network and categorizes top call paths by jitter, latency, MOS and packet loss.

 

VoIP Monitor Overview

VoIP Monitor Overview

This list shows the path, MOS, RTT, latency, jitter and packet loss details for each of the different paths present in VoIP network. These values are updated at each poll. The availability and next poll time is also shown.

 

Min/Max MOS History Graph

Min/Max MOS History Graph

The MOS (Mean Opinion Score) history graph gives Min/Max jitter values over time to measure the quality of calls expressed on a scale from 1 to 5. This graph helps to know the call quality statistics for the selected path.

 

VoIP Availability Graph

VoIP Availability Graph

The availability graph displays the availability status as a percentage for a period of time and unreachability of the polled data.

 

VoIP Positive and Negative Jitter Graph

VoIP Positive and Negative Jitter Graph

Monitor jitter in real-time for each path from source to destination and drill down for any sudden spike in jitter graph.

 

VoIP Round Trip Time History Graph

VoIP Round Trip Time History Graph

Monitor Min, Max and Average RTT to check for time delay in the communication for troubleshooting voice quality degradation.

 

VoIP Packet Loss Graph

VoIP Packet Loss Graph

Monitor packet loss to know how many packets are being dropped and how does it affect the quality of the call connection established.

 

VoIP Error Statistics Graph

VoIP Error Statistics Graph

Monitor errors such as late packet arrival, MIA and out of sequence for the selected time period to detect bad communication connections.

Scenario

A company based in the United States recently moved from PSTN to VoIP based technology. The network manager has been receiving lots of complaint regarding voice communication. Their staff complain of drop in quality of voice communications. The drop in quality directly reflects in the form of broken communication and talk-over effects. The network manager is not able to zero in on the source of the problem. He is suggested to try ManageEngine NetFlow Analyzer which has VoIP monitoring feature. The network manager installs ManageEngine NetFlow Analyzer to monitor the bandwidth and identify the reasons for the drop in the quality of voice communications. The monitoring tool uses Cisco's IP SLA to monitor VoIP. VoIP monitoring results in displaying data by jitter, latency, packet loss and MOS. The network manager uses ManageEngine NetFlow Analyzer VoIP monitor to view the top call performances by location. He clicks on a top call path to view the call path details and threshold details. He also views the graphical representation of MOS, jitter, latency, packet loss and round trip time of that particular call path. The network is monitored at different time intervals and the data collected. These data are used to assess the performance of the network and in troubleshooting.

Note: Reporting on VoIP is available as an Add-On. It will be available during the 30 day trial period, after which separate license has to applied for VoIP add-on.

Download | Online Demo | Product overview

NetFlow Analyzer is a NetFlow, sFlow, JFLow (and more) collector and analyzing engine integrated together. NetFlow Analyzer is a software (for windows and linux), does not require any hardware probes, which can be downloaded, used in your network environment and can be evaluated for 30 days. Go through the following useful links for better understanding of how NetFlow Analyzer can help you in understanding your network traffic and bandwidth utilization.