Healthy VoIP Nets�Part XXXIX�Network Management Architectures: ClearSight Networks

ClearSight Networks, Inc., headquartered in Fremont, Calif., is a provider of network monitoring and analysis tools for real-time application troubleshooting.

The company was founded in early 2001 by former employees of Network General and founders of Cinco Networks. (Cinco was acquired by Network General in 1997.) Previously known as AppDancer Networks, ClearSight Networks received a majority investment in April of 2003 from Japan-based Toyo, and was then placed under new management.

ClearSight claims to be the only company that identifies network problems at the application layer, enabling IT administrators to easily and immediately visualize and pinpoint the source of network problems, leading to faster resolution that ensures business continuity.

The company is privately held, and has about 60 employees. Its products are sold worldwide through a direct and reseller channel.

The ClearSight Analyzer product line include the ClearSight Analyzers, the ClearSight Distributed remote monitoring system, and the Network Time Machine, a data capture and analysis system.

The ClearSight Analyzer is an advanced network monitoring and troubleshooting tool that illustrates network activity via a simple, intuitive user interface. This analyzer includes support for triple-play systems, including IPTV.

The ClearSight Analyzer Gigabit and Clearsight Analyzer 10G support networks of up to 10 Gigabit Ethernet capacity. The systems support the analysis of various signaling protocols including SIP, H.323, Cisco SCCP, MGCP, MEGACO, and RTSP.

The VoIP protocol decodes supported include: H.323, SIP, MGCP, MEGACO or H.248, SCCP (“Skinny”), RTSP, MSN, SKYPE and RTP/RTCP. In total, the Clearsight Analyzer supports nearly 1,000 protocol decodes, which the company claims is one of the most extensive lists in the industry.

One of the strong suits of the ClearSight Analyzer is its ability to provide a ladder display of the communication sequences; call reports, alarms, and packet decode functions (see Figure 1).

It can also generate a QoS report for a VoIP call simply by selecting the desired call and clicking the [Report] tab (see Figure 2). The QoS report includes analysis of voice quality parameters (including packet loss, jitter, R-value, and MOS) stated as VQFactor™ and MDI for a video stream.

The system also includes a VoIP Call Log Browser, which can extract call history (start time, caller, callee, MOS, and duration) from the VoIP call log information stored in ClearSight Analyzer’s history database based on specified conditions, and list the results in this report. Time range, call duration, and MOS value can be combined as extraction conditions. The extracted call log can then be exported in CSV (comma-separated values) format, and can also be compiled in a separate spreadsheet program (see Figure 3).

The analyzer also measures audio or video quality for each RTP stream and displays detailed statistical information as a result. MOS and R-Value are supported as QoS metrics for voice; VQFactor (a video quality metric developed with ClearSight’s patent pending algorithm) and the Media Delivery Index (MDI—an indicator for video transport performance) are supported for video (see Figure 4).

ClearSight Analyzer also supports the performance analysis and troubleshooting of video streams in IPTV environments. Presenting an IPTV channel zapping analysis graph, the analyzer categorizes multicast streams under IPTV environments into each channel and graphically show changes in the packet rate (see Figure 5).

ClearSight Distributed is a distributed system with a next-generation application flow analyzer. Using the central Agent Manager, it allows for remote network monitoring, application performance analysis, and troubleshooting for multiple LAN segments that are physically separated from one another. Monitoring and analysis of network traffic is done within a Remote Agent, which minimizes the management traffic overhead between the manager and probe. The Agent detects malfunctions on the network and generates alarms, which can include a variety of actions, such as sending an email, page, or SNMP trap message, or the execution of a Java script.

The ClearSight Packet Generator is a software program for transmitting traffic via 10/100Mb Ethernet from a Windows PC. The software supports single packet mode for repeatedly sending the same packet, and buffer mode for regenerating traffic captured from the actual network. The Packet Generator can be used in conjunction with ClearSight Analyzer to test transmission of packets across a network during network installation. The number of packets and transmission rate can be adjusted from Packet Generator and the received packets monitored by ClearSight Analyzer after passing across the network and network devices.

Further details on the Clearsight Networks architecture and products can be found at Our next tutorial will continue our examination of vendors’ network management architectures.

Copyright Acknowledgement: © 2008 DigiNet Corporation ®, All Rights Reserved

Author’s Biography
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.

Latest Articles

Follow Us On Social Media

Explore More