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The end-to-end context represents the factors that influence the communication performance between the tenant-side client and the fog server. Essentially, a system can measure the end-to-end context based on the server context and mobility context. Hence, one can consider that the end-to-end context is a second level context. In summary, end-to-end context involves the following factors [26, 64]:

 Signal strength. A dynamic factor at run-time in many cases, such as LV-fog and UE-fog environments where the density of the wireless network objects is high and hence, they can interfere the signal strength of one another. Therefore, tenants need to consider the signal strength when they intend to measure the connectivity between the fog server and the tenant-side client.

 Encounter chance and Inter-contact time. Represent the possibility of the fog server and the tenant-side client to successfully communicate and how long they can maintain the connection for the current stage and next stage. Specifically, it influences the decision of whether the tenants should deploy the application on the fog server for their clients or not, and whether the tenant-side clients can utilize the fog servers for task distribution or not.