Ready for VoIP: Network Management Architectures: NetQoS
VoIP Monitor, a component of NetQoS Performance Center, is a comprehensive solution and even provides specific CallManager readouts.
The company was founded to provide better ways of monitoring and improving the delivery of these applications, and to develop solutions that could scale to support very large networking infrastructures.
Unlike the traditional fault-based network management approaches, NetQoS takes a performance-first approach to managing network infrastructures, including systems that provide for end-to-end performance monitoring, traffic analysis, device performance management, IT cost accounting, and retrospective network analysis.
The NetQoS Performance Center product suite is a complete network performance monitoring and management solution with a single web console that provides a top-down view of all applications-data, voice and video-that are running on the network infrastructure. The solution quantifies network infrastructure performance, including end-to-end response times, traffic analysis, device performance monitoring, and VoIP performance management. With this comprehensive data, IT personnel in large, complex networks can isolate and troubleshoot problems more quickly and efficiently, analyze and plan for the impact of change, and monitor and manage application delivery.
The console provides access to four key product solutions: the NetQoS SuperAgent, for end-to-end performance monitoring; the NetQoS VoIP Monitor, for VoIP network performance monitoring; the NetQoS ReporterAnalyzer, for traffic analysis; and the NetQoS NetVoyant, for device performance management.
NetQoS VoIP Monitor is a network-based call-setup- and call-quality-monitoring solution that generates data about the network impairments that are affecting the Quality of User Experience. This solution unites VoIP quality of service with network performance, to provide metrics for end-user quality of experience and facilitate targeted troubleshooting.
VoIP Monitor provides insight into two of the most important components of VoIP quality: call setup operations (such as time to dial tone and post-dial delay) and audio quality (the Mean Opinion Score, or MOS), and underlying network impairments. By tracking end user call quality, providing alerts on call performance issues, and isolating the cause of VoIP problems to the network source, VoIP Monitor helps organizations improve performance through faster troubleshooting. This includes graphical displays of the call quality and MOS, call quality trends, call performance by location, and call performance by gateway (see Figure 1).
The product also lets network engineers and IP telephony management assess the performance of their Cisco Unified Communications Manager (CallManager) IP PBX by tracking, evaluating, and reporting on key metrics without deploying server agents or probes. For every call, VoIP Monitor reports on user call quality and the underlying network performance metrics associated with it. VoIP Monitor also breaks out performance data from the IP and PSTN legs of calls that pass through voice gateways traveling to endpoints in the PSTN. This data lets IT organizations know if the network is responsible for less-than-optimal call quality.
VoIP Monitor operates by performing passive, or "agentless," monitoring of traffic passing through a switch. By passively observing the headers of VoIP-related packets as they pass from the network into the CallManager cluster and out again, it can measure network delay, server response time, jitter, and other key network metrics. From that data, it automatically discovers the servers, voice gateways, and IP telephones that are running on a network, calculates VoIP call setup performance based on packet header information, and uses thresholds to detect performance exceptions.
VoIP Monitor version 1.1 includes automatic and on-demand problem investigation, such that when a performance threshold is exceeded, the system can automatically initiate an investigation into the source of the problem, tracing the call signaling path and comparing it to a baseline; capacity planning reports, which provide reports for tracking call activity, including information about call volume, call quality, call failures, grade of service, and gateway utilization; plus support for Cisco SIP phones using the SIP call setup protocol.
Further details on the NetQoS architecture and products can be found at www.netqos.com.Our next tutorial will continue our examination of vendors' network management architectures.
Mark A. Miller, P.E., is President of DigiNet Corporation, a Denver-based consulting engineering firm. He is the author of many books on networking technologies, including Voice over IP Technologies, and Internet Technologies Handbook, both published by John Wiley & Sons.
Article courtesy of Enterprise VoIP Planet, © 2008 DigiNet Corporation, All Rights Reserved