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Server discoverability is a specific requirement for the multitenancy fog services, and it involves two phases.

 Multitenancy fog service provider discovery. Presents the phase when the tenants intend to discover feasible fog service providers for deploying their applications. Commonly, based on the experience of the cloud service business model, it is likely that the tenants would discover the providers via the indexing services (e.g. Google searching). Alternatively, the providers may establish a federated service registry for the service discovery. Furthermore, the provider may follow the open standard-based service description mechanism or interface (e.g. ETSI – MEC standard) to describe their fog services toward helping the tenants to discover the service that matches to their requirements.

 Runtime fog server discovery. Presents the runtime service discovery phase for the fog applications. In general, the fog applications hosted on the fog servers, need to perform seamless interaction with the end-devices on the move. Besides the mobility schemes that help the tenants to identify the movement of the end-devices, tenants need a corresponding mechanism that can help the end-devices to continuously discover and to connect to the new fog servers automatically, without any inference from the end-users. Therefore, the fog servers need to support the corresponding API that allows the tenants to configure the application process/task handover and migration mechanism among the fog nodes. Commonly, if such an API support is not available, tenants have to enable the corresponding mechanisms from the higher layer of the application, which may result in an inefficient tenancy cost and operational performance.