Our previous tutorial considered some example products in our first three categories of VoIP network management tools: SNMP-based enterprise network management, protocol analyzers and performance/QoS monitors. In this tutorial we will review the last of our six categories: agent/probes, traffic simulators, and network design/optimization software.
Agent/Probe: Most network managers can’t afford to replicate their test equipment at every location, so most rely on a central location where most of the intelligence resides, and some type of data collection device for remote locations or branch offices. In some cases, this technology is known as RMON (remote monitoring)—developed in the late 1990s as an enhancement to SNMP-based network management. In any event, that remote device, which may be called an agent or a probe, monitors the remote network and its data, and then reports key statistics back to the central system at headquarters.
Telchemy, Inc. has done considerable work in the areas of VoIP, IPTV, and videoconferencing performance, to the extent that over 30 million units of their VQmon software have been shipped to over 100 equipment vendors and incorporated into their products. Three different versions of VQmon have been developed: VQmon/EP (endpoint), which is integrated into IP phones, gateways, cellular handsets, etc.; VQmon/SA (stream analysis), which is integrated into mid-stream devices, such as probes, analyzers, routers, and so on; and VQmon/HD for real time IPTV and IP videoconferencing performance metrics.
Traffic Simulators: What happens if you buy a new video conferencing system for your existing network, and then wonder—Can it handle the load, or will we have to add bandwidth to keep the existing voice and data applications running effectively? Unless you want to just trust your luck, putting a traffic simulator on the network is the best way to test out the new configuration in advance, and see if the network can support the traffic. Spirent Communications makes a number of tools that can provide answers to these questions, including the Abacus 50 Ethernet Test System that provides VoIP analysis, signaling, and media traffic generation, the Abacus 5000 Session Border Controller Test Solution, and the SmartBits traffic generation tool that can included automated test scripts. Larger enterprises should consider these tools prior to new technology rollouts. Brix Networks provides a distributed converged service assurance solution that includes both hardware and software components, called the Brix System. The architecture includes six components: BrixWorx, a service assurance correlation and analysis software engine; Brix Verifiers, software agents that are monitoring sources; BrixCall, voice quality and performance management software; BrixVision, IP video quality and performance management software; BrixNGN, a software tool that verifies the quality of next-generation networks; and BrixView, the analytics and business intelligence software. The Brix System can also integrate with third party applications, such as operational support systems (OSS), fault management, trouble ticketing systems and data gather tools.
Network Design/Optimization Software: the tools in this category drew the smallest number of responses—perhaps because they are based on the theories of traffic analysis, and peppered with terms such as erlangs and busy hour calls. If you are designing a multi-location environment for tens of thousands of end users, such a tool is essential. But even managers of smaller systems can benefit from some of the information that they provide. Two products, at polar extremes on the price/performance scale, are worthy of note. The more modest tool is the Windows-based VoIP Select from Westbay Engineers, Ltd., which allows you to calculate bandwidth consumption based upon codec selection, determine the effect on bandwidth of transmitting VoIP over Ethernet or Frame Relay, and other calculations. VoIP Select is priced at $175.00 and is worth every penny that you spend. At the high end are the OPNET Technologies suite of products that are designed to simulate the performance of applications, provide end-user experience monitoring, and real-time network analytics. The OPNET software is available in modules, some of which can run into the tens of thousands of dollars, and require a week or more in class to learn how to use. But when you are migrating tens of thousands of end users to a VoIP network, it is comforting to know that there is some solid mathematics behind your design decisions.
Our next tutorial will conclude our Buyer’s Guide to VoIP network management solutions, with a matrix of all the vendors we reviewed and the network management categories that they support.
Copyright Acknowledgement: © 2009 DigiNet Corporation®, All Rights Reserved
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.