Integrated Performance Analysis Technology for VoIP, Videoconferencing, and IPTV

Telchemy's VQmon® is a modular performance analysis software agent that supports VoIP, IP Videoconferencing, IPTV, and Video Streaming services. It is a compact, portable software library that can be integrated into a wide range of host environments—including probes, routers, ONUs, handheld test devices, IPTV set-top boxes, and videoconferencing equipment—providing real-time quality analysis of IP voice and/or video streams with low impact on host resources including CPU and memory.

VQmon is available as a compiled binary for Windows, Linux, Solaris, BSD, and standard processor environments. The VQmon library includes both interface-based and stream-based APIs, enabling host applications to non-intrusively monitor single or multiple concurrent voice or video streams and to obtain real-time QoE scores and a rich set of diagnostic metrics on a per-interface, per-stream, or per-call/per-video session basis. Key API functions enable host applications to initialize streams, indicate received packets, retrieve quality metrics, and terminate streams.

VQmon is modular software that can be licensed to support monitoring of VoIP, Videoconferencing, IPTV, Video Streaming, or any combination of these services.

VoIP Performance Monitoring

In VoIP performance monitoring applications, VQmon efficiently analyzes multiple parallel packet voice streams and provides estimated call quality scores (MOS and R-factor) and detailed diagnostics for each RTP stream, at the end of each call or at any point during a call. VQmon examines each voice 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 call quality scores and diagnostic data.

VQmon can be used on its own for mid-stream call monitoring applications, or as part of an end-to-end monitoring architecture—i.e., in conjunction with Telchemy's VQmon/EP performance analysis technology embedded into VoIP endpoints such as IP phones and gateways. VQmon is fully compatible with VQmon/EP and produces a range of additional packet- and jitter-buffer-related statistics. VQmon supports full RTCP XR VoIP metrics payload decoding and is able to determine round-trip delay from either RTCP or RTCP XR. VQmon generates both listening and conversational quality MOS scores and R factors and a wide range of diagnostic data, making these available through an API as raw metrics, RTCP XR and SIP RTCP Summary Report payloads.

VQmon is the most widely used and deployed VoIP analysis technology, forming the core of most of the industry's VoIP probes and analyzers. VQmon is 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).

IP Videoconferencing / IPTV Performance Monitoring

In IP video monitoring applications, VQmon efficiently analyzes multiple parallel packet video streams (RTP or MPEG-2 Transport), and generates real-time perceptual quality scores and a detailed set of diagnostic metrics for each monitored stream. The VQmon code is compact and efficient, and is specifically designed for integration into network analyzers, IPTV probes, residential gateways, IP set-top boxes, videoconferencing and test equipment. Quality metrics can be produced at the end of each video session or at any point during a session, providing much greater insight than other methods that only report average levels of packet loss/jitter upon session termination.

Key advantages of VQmon include:

• Analyzes scrambled / encrypted video streams without decoding - preserves DRM/copyright requirements
• Identifies Group of Pictures (GoP) structure and analyzes impact of impairments on I, B, and P frames for more accurate estimated QoE scores
• Extracts high-level content descriptors (levels of detail, motion, panning) and generates alerts for abnormal content such as frozen or blank video

TCP Video Streaming

VQmon is able to analyze key video streaming protocols, including Adobe, Apple and Microsoft formats. VQmon analyzes the TCP stream carrying the video, the playout buffer dynamics and the video stream itself. Analysis of the TCP stream provides key information on network bandwidth, the impact of congestion and server performance. Real time emulation of the playout buffer allows buffer fill and empty rates to be measured, and detects if buffer levels get too low, which leads to gaps in playout. Video stream analysis provides video quality estimation and key information on the encoded stream. VQmon computes MOS scores (measures of QoE) that reflect video encoding parameters, video resolution and playout gaps using an advanced perceptual model.

For more information on VQmon for TCP Video Streaming, click here.

VQmon Features and Specifications

• Compact, efficient code size - typically approximately 136 KB (compiled binary) depending on features licensed
• CPU load typically under 0.5 MIPS per active stream
• Processor: 32-bit generic integer processor
• Analyzes voice/video RTP streams and MPEG-2 Transport video streams
• QoE Scores for VoIP: Listening and Conversational Quality MOS (MOS-LQ, MOS-CQ) and R-factors ( R-LQ, R-CQ)
• QoE Scores for Video: Video, Audio, and Audio-Video MOS (MOS-V, MOS-A, MOS-AV) and Video Service Transmission Quality (VSTQ)
• Burst and Gap R-factor Scores for Voice (R-Gap, R-Burst)
• Narrowband and Wideband R and MOS Scores
• Degradation factors - % degradation due to packet loss, discard, delay, codec type, frame resolution, frame rate, GoP size, etc.
• Burst and Gap Loss/Discard Statistics
• Lost, Discarded, Out-of-sequence, Duplicate packet statistics
• PPDV (RFC3550), MAPDV (G.1020) and Y.1540 Jitter Metrics
• TR 101 290 Decodability Metrics for Video
• Support for a wide range of ITU, cellular, industry-standard, and proprietary voice, video, and audio codecs
• Cumulative and Interval Metrics

For more information about integrating VQmon performance analysis technology into your product line, contact Telchemy.

For information on VQmon accuracy and performance, including the results of tests comparing VQmon's accuracy with that of other testing methods, click here.