By Benjamin Ellis and Mike Hollier

This article will address the future of IP technology and need-to-know enterprise IP technology information as it relates to IP migration and achieving optimal quality of experience (QoE) levels across IP services.

Lack of attention to end-user quality of experience (QoE) across the service provider, mobile operator and enterprise communities could be the downfall to mass IP service adoption. If heightened attention on service price cuts, neglected advancements in test and measurement technology and poor QoE management capabilities continue, the big promises around reduced costs and improved productivity will never come to light.

End-users have historically steered clear of IP networks and VoIP deployment because landlines seem to do the job better – despite enticing price points. While service providers are, to their credit, attempting to improve the quality of services like VoIP and, more recently, IPTV, they may be using the wrong methods. This article sheds light on the value of QoE capabilities and its critical impact on the maturation and saturation of IP services.

Quality Measurement

The key to measurement is using the most cost effective and time efficient approach, enabled by the right technology. By utilizing the latest technologies for rating QoE, service providers can move away from outdated subjective test methods and toward objective measurement of customer experience. QoE enables service providers to identify and track in real-time metrics that correlate with end-user experience, and then execute one step further by adjusting services accordingly.  To better understand objective testing methods as related to IP-based services like VoIP and IPTV, we must first come to grips with the shortcomings of subjective testing.

Subjective Measurement Shortcomings

Subjectively testing speech quality in voice and video calls requires service providers to select a panel of “typical” end-users and play a set of voice or video samples for each of them. The service providers then ask each user to rate the quality of the voice and video samples by employing a Mean Opinion Score (MOS) from one to five. To obtain a valid measurement the users must experience each sample under different testing environments to simulate real-world scenarios. Once the tests are complete the service providers compile the subjective test data and analyze it to rate the performance in terms of real-world service quality. Service providers, as well as equipment vendors, continue to rely on subjective testing to validate perceived service or product quality.

While subjective testing provides valuable information, its methodological drawbacks are too numerous to reliably shape an enhanced IP technology future. Subjective testing is extremely time consuming to perform and must be designed and executed with the highest regard to variables that could alter the perception of quality. This form of testing is also very expensive because it requires a specially designed testing facility, purpose-built to conduct subjective quality tests.

Objective Measurement Benefits

A cost-effective alternative to subjective testing for voice and video quality assessment is objective measurement. Unlike subjective tests, objective methods do not require a panel of human testers to analyze performance impairments and network parameters to produce a final MOS. Objective measurements are repeatable, efficient and fast. There are two main classes: intrusive and non-intrusive.