Spirent Communications, a provider of integrated performance analysis and service assurance systems for next-generation network technologies, today announced that it has integrated V-Factor) into the Spirent IPTV Quality of Experience (QoE) Test System. V-Factor, developed by QoSmetrics, is an implementation of the Moving Picture Quality Metric (MPQM) standard for network-delivered video assessment and displaces the older, primitive Media Delivery Index (MDI) approach.

By employing the Spirent IPTV QoE Test System with V-Factor, network equipment manufacturers and service providers can rapidly deliver the highest quality IPTV service. By accurately anticipating subscriber's IPTV service experience, V-Factor is critical to the successful launch of IPTV networks and services. This drives service adoption, increases subscriber loyalty and reduces churn. Hitachi is one of the first IPTV network equipment manufacturers to employ Spirent's V-Factor enabled test system.

The Spirent IPTV QoE Test System along with V-Factor technology provides a higher class of fidelity testing metrics. It determines video quality as perceived by a subscriber and offers the highest correlation with user's actual quality of experience. V-Factor, which also includes audio performance assurance, takes into account network impairments such as delay variation and packet loss episodes that impact the video buffer used to restitute a video image as well as image complexity and the type of codec used. The technology enables the service provider to understand how network performance issues impact this perceived quality, in advance of the service being launched. Obsolescent testing metrics such as MDI merely attempt to infer subscriber QoE based on network performance indicators.

"MDI only looks at two network parameters and is blind to video stream content making it unsuitable for video quality assessment," said Bahaa Moukadam, vice president, IP Telephony, Spirent Communication. "The Spirent test system combined with V-Factor looks at both network impairments and video stream content to report a video MOS score and a wide range of relevant statistics for comprehensive diagnostics of network and coding problems enabling service providers to successfully rollout IPTV services."

V-Factor is an objective measurement system that reproduces the subjective experience of the human observer. Network-based metrics are only capable of suggesting a coarse grade of subscriber QoE and are not sufficient for performance evaluation of video services like IPTV, especially in the context of a highly competitive broadband video market. MPQM, by comparison, is based on an objective evaluation method that is capable of filtering network-induced quality of degradation by properties of human vision.

"We're delighted at the opportunity to work with Spirent Communications to deliver such strong IPTV testing solutions for service providers and network equipment manufacturers," said Yves Cognet, chairman, QoSmetrics. "Our V-Factor technology has proven itself to be adaptable and deployable in everything from the core to the set top. Integrating this technology into the Spirent IPTV QoS Test System is certainly a key milestone for the IPTV test market."