Quality of Experience (QoE) relates to how users perceive the quality of an application. To capture such a subjective measure, either by subjective tests or via objective tools, is an art on its own. Given the importance of measuring users¿ satisfaction to service providers, research on QoE took flight in recent years. In this paper we present an overview of various techniques for measuring QoE, thereby mostly focusing on freely available tools and methodologies.@en

In an earlier paper we showed, that perceived quality of channel zapping is related to the perceived quality of download time of web browsing, as suggested by ITU-T Rec.G.1030. We showed this by performing subjective tests resulting in an excellent fit with a 0.99 correlation. This was what we call a lean forward experiment and gave the rule of thumb result that the zapping time must be less than 0.43 sec to be good ( > 3.5 on the MOS scale). To validate the model we have done new subjective experiments. These experiments included lean backwards zapping i.e. sitting in a sofa with a remote control. The subjects are more forgiving in this case and the requirement could be relaxed to 0.67 sec. We also conducted subjective experiments where the zapping times are varying. We found that the MOS rating decreases if zapping delay times are varying. In our experiments we assumed uniformly distributed delays, where the variance cannot be larger than the mean delay. We found that in order to obtain a MOS rating of at least 3.5, that the maximum allowed variance, and thus also the maximum allowed mean zapping delay, is 0.46 sec.@en

The end user experience of service quality is critical to the success of a service provider's IPTV deployment program. A key element involved in validating IPTV quality of experience (QoE) is how qiuckly and reliably users can change TV channels, often referred to as channel zapping. Currently there is no knowledge about the explicit relation between zapping time and the user perceived quality as expressed as a Mean Opinion Score (MOS). We have proposed a model where the MOS depends on the zapping time on a logarithmic scale. In order to validate our model we have conducted a number of subjective tests in order to get insight in this relation. The tests were performed by 21 test subjects at TNO and at Acreo. It turns out that the correlation between the subjective data and the perceptive model is very high (0.99). Therefore we conlcude that our perceptive model is very useful for assesing the perceived quality of zapping. The result is not limited to IPTV but applies to any type of TV service with channel switching times that are not instantaneous, regardless whether it is terrestial or satellite based.@en

End-to-end tests and evalutations, as a proof of concept, are essential tool in the development of innovative telecommunication concepts and platforms. Within the integrated project MUSE (Multiservice access erverywhere) we have put extensive efforts in defining a complete test suite for full-service end-to-end testing. This test suite describes what and how to test. In this paper we focus on one specific aspect of the test suite i.e. perceived Quality of Service. The test suite for Voice over IP is presented and the results from a test setup between the Netherlands and Sweden, where the perceived QoS have been estimated for a particular network connection.@en