An edge data center can host applications that require low-latency access to nearby end devices. If the resource requirements of the applications exceed the capacity of the edge data center, some non-latency-critical application components may be offloaded to the cloud. Such offloading may incur financial costs both for the use of cloud resources and for data transfer between the edge data center and the cloud. Moreover, such offloading may violate data protection requirements if components process sensitive data. The operator of the edge data center has to decide which components to keep in the edge data center and which ones to offload to the cloud. In this paper, we formalize this problem and prove that it is strongly NP-hard. We introduce an optimization algorithm that is fast enough to be run online for dynamic and automatic offloading decisions, guarantees that the solution satisfies hard constraints regarding latency, data protection, and capacity, and achieves near-optimal costs. We also show how the algorithm can be extended to handle multiple edge data centers. Experiments show that the cost of the solution found by our algorithm is on average only 2.7% higher than the optimum.

5G imposes versatile requirements on radio and mobile core network. Such requirements can be supported by parallel so-called slices, each implementing a service-tailored network architecture. This paper shows how such architectures can be implemented with the evolved packet core (EPC). We furthermore provide a cost analysis of an EPC based, sliced network deployment in Japan for 5G services. It shows that the main cost driver are low latency services, as these require a highly distributed infrastructure. For the expected massive number of IoT devices, a centralized infrastructure keeps costs surprisingly cheap in contrast. Overall, the paper shows that EPC is well suited for the 5G challenges, which is relevant especially for the first 5G deployments in 2020.

Requirements and use cases for the 5G era are demanding in key dimensions such as throughput, latency, scalability and automation. From these, an end-to-end architectural vision has been developed in a holistic way and including novel architectural concepts including 5G access domain and 5G era horizontal layers in conjunction with cloud, software defined and cognitive networks transformation. End-to-end architecture for the 5G era is decomposed in a systematic manner, key attributes and characteristics of the associated architectural domains are described.