This Recommendation provides the methodology for the assessment of metrics for the end-to-end quality of service (QoS) of mobile communication services on board vehicles moving along a defined route, i.e., trains as well as road vehicles, and in particular public transport. This metric is a measure for call stability or retainability, i.e., it represents the probability that a telephone call with a pre-defined duration can be completed successfully.

The metric exploits specific properties of respective use cases and allows for a holistic, end user centric point of view on related mobile network performance characteristics. The underlying model consists of two parts:

• a computation methodology which derives spatially resolved information from measurement data acquired by conventional mobile network testing, and

• a methodology which uses the data created to compute respective high-level QoS indicators.

The methodology also produces spatially resolved information about local call stability and is therefore useful for network optimization.

The recommended methodology focuses on aspects of voice telephony. However, an extension of this methodology to aspects of mobile data communication is possible and will be taken into account in a future revision of the present Recommendation.