DVQattest provides compact, efficient software test agents that can be easily installed onto PCs or servers in key locations throughout an Enterprise network or quickly downloaded to residential/Hosted PBX subscriber desktops. These powerful and highly configurable DVQattest Agents can both generate and receive multiple parallel RTP media streams, allowing them to accurately simulate voice calls and video sessions reflecting the real-world traffic conditions created by a wide range of IP voice and video services. DVQattest Agents can also perform a number of network diagnostic tests, identifying and reporting problem conditions—such as congestion or duplex mismatch along the network path—that can degrade service quality.

DVQattest Agents employ integrated VQmon® performance analysis technology to calculate accurate quality scores and a rich set of media, network, and signaling performance metrics for every voice call, video session, and network test. When problems are detected, DVQattest’s VQexpert^TM Expert Analysis technology provides a straightforward text diagnosis and indicates the specific factors contributing to quality degradation—making it easy to quickly troubleshoot problems without the need to interpret complex test metrics.

DVQattest’s detailed quality and performance metrics and Expert Analysis diagnostics are displayed in real time in the interactive DVQattest Controller GUI.

Distributed Active Testing Solution for Enterprise or Service Provider Network Environments

DVQattest is available in two versions, customized for either Enterprise or Residential/Hosted PBX service provider applications.

DVQattest/EN is designed for Enterprise network environments and is ideal for both pre-deployment testing of VoIP/IP Videoconferencing services and advanced problem diagnosis/service level monitoring of existing voice and video services. DVQattest Agents can be installed on Windows or Linux servers and PCs anywhere in the Enterprise network, including remote branch offices and teleworker locations, running unobtrusively as background tasks (either Windows service or Linux daemon). Each agent supports up to 200 simultaneous test calls— depending on the host machine and licensing options—simultaneously reporting quality scores and performance data back to the central DVQattest Controller Java application, which is also used to configure agents and test plans and to review system status, alerts and events.

DVQattest/RE gives Residential and Hosted PBX service providers a convenient, effective way to perform subscriber pre-signup qualification and to resolve problems affecting existing broadband VoIP/IPTV customers. DVQattest/RE’s small, powerful test agents can be quickly configured using the provided Agent Builder Web interface and downloaded to subscriber Windows or Macintosh desktops via an automatically generated emailed link. Once executed, the downloaded agent contacts a test server on the service provider network and executes one or more preselected voice, video, or network diagnostic tests. Quality scores and performance metrics are gathered in real time at both ends of the service link and reported to the cross-platform DVQattest Controller GUI. Upon completion of the test(s), the downloaded agent deletes itself from the subscriber’s machine. (Agents can also be installed as a service for ongoing test applications.)

DVQattest/RE allows service providers to gather detailed performance data directly from the customer premises, even when behind a firewall—making it easier to isolate and troubleshoot service problems that originate from the subscriber LAN.

How DVQattest Works

DVQattest generates RTP streams containing speech or IP video payloads and automatically inserts RTCP SR, RR, and XR messages. At the receiving end of each stream, DVQattest examines each voice or video packet, accurately predicts which packets would be lost or discarded using a jitter buffer emulator, measures the distribution of lost and discarded packets, and produces MOS quality scores and diagnostic data. In addition to the same rich set of diagnostic data produced by VQmon/EP, DVQattest also produces a range of additional packet- and jitter-buffer-related statistics. DVQattest is small and fast, requiring only a fraction of a MIP for each VoIP call stream.

DVQattest's quality scores and diagnostic data are also available through an API as raw metrics, RTCP XR, and SIP QoS Report payloads. DVQattest's quality measurements are provided by VQmon, an advanced VoIP perceptual quality estimation algorithm that incorporates support for key international standards including ITU-T P.564, ITU-T G.107, ITU-T G.1020, ETSI TS 101 329-5 Annex E and IETF RFC 3611. VQmon incorporates support for time varying IP impairments (typically caused by network congestion) and has been independently shown to provide significantly more accurate and stable metrics than other algorithms such as G.107 (E Model).

Some of DVQattest's features include:

• Listening and Conversational Quality MOS scores for Voice - MOS-LQ, MOS-CQ
• Picture, Audio, and Multimedia Quality MOS scores for Video - MOS-V, MOS-A, MOS-AV
• Video Service Transmission Quality, Picture Quality, and Media Quality - VSTQ, VSPQ, VSMQ
• Burst and Gap Scores indicating quality during degraded vs. normal periods - MOS-Gap, MOS-Burst
• Burst and Gap Packet Loss/Discard Statistics
• Degradation factors - % degradation due to loss, discard, delay, codec, etc.
• Lost, Discarded, Out-of-sequence, Duplicate packet statistics
• VQexpert^TM Network Diagnostics - detects duplex mismatch, LAN congestion, access link congestion, link failures, and more
• PPDV (RFC3550), MAPDV (G.1020) and Y.1540 Jitter Metrics
• Modem/Fax Metrics - Reliability and Throughput
• Support for a wide range of ITU, cellular, industry standard and proprietary codecs
• Cumulative and Interval Metrics

For more information, refer to the DVQattest Product Brochure or contact us.