More and more companies are increasingly using cloud services. Accordingly, the decision for a cloud service provider is crucial for the potentially added value of the cloud service to the company, which is why the selection should be subject to a well-planned process, and the final decision must be made carefully. Since cloud service providers make resources available via the internet, performance parameters are important for assessing cloud service providers and play an important role in the decision-making process. Therefore, this paper addresses the question of which network performance metrics are relevant for selecting a cloud service provider and how these metrics can be collected and evaluated. It provides and instantiates an assessment method that can be used as guidance for cloud service provider selection. Thereby, the results show the possibility of testing and evaluating technical instead of merely qualitative aspects of infrastructure provided by cloud service, which is a contribution to existing literature in the field.