Anteneh A. Gebremariam

Software defined and virtualized wireless access in future wireless networks: scenarios and standards

Future wireless networks are expected to provide augmented and data-intensive services in a multi-vendor multi-proprietor scenario. This scenario introduces relevant challenges to the networking infrastructure, especially in terms of flexibility and interoperability, that could be addressed by extending the concept of Virtualization and Software Defined Networking (SDN) to the wireless or wired-cum-wireless world. This paper provides a review of the perspectives to the extension of the SDN paradigm in the wireless domain by identifying current trends and proposed solutions, and providing the existing major standardization efforts and future trends in the field.

A Software-Defined Device-to-Device Communication Architecture for Public Safety Applications in 5G Networks

The device-to-device (D2D) communication paradigm in 5G networks provides an effective infrastructure to enable different smart city applications such as public safety. In future smart cities, dense deployment of wireless sensor networks (WSNs) can be integrated with 5G networks using D2D communication. D2D communication enables direct communication between nearby user equipments (UEs) using cellular or ad hoc links, thereby improving the spectrum utilization, system throughput, and energy efficiency of the network. In this paper, we propose a hierarchal D2D communication architecture where a centralized software-defined network (SDN) controller communicates with the cloud head to reduce the number of requested long-term evolution (LTE) communication links, thereby improving energy consumption. The concept of local and central controller enables our architecture to work in case of infrastructure damage and hotspot traffic situation. The architecture helps to maintain the communication between disaster victims and first responders by installing multi-hop routing path with the support of the SDN controller. In addition, we highlight the robustness and potential of our architecture by presenting a public safety scenario, where a part of the network is offline due to extraordinary events such as disaster or terrorist attacks.

End-to-end Network Slicing for 5G Mobile Networks

The research and development (R&D) and the standardization of the 5th Generation (5G) mobile networking technologies are proceeding at a rapid pace all around the world. In this paper, we introduce the emerging concept of network slicing that is considered one of the most significant technology challenges for 5G mobile networking infrastructure, summarize our preliminary research efforts to enable end-to-end network slicing for 5G mobile networking, and finally discuss application use cases that should drive the designs of the infrastructure of network slicing.

A framework for interference control in Software-Defined mobile radio networks

To cope up with the booming of data traffic and to accommodate new and emerging technologies such as machine-type communications, the 5th Generation (5G) of mobile networks must be empowered with efficient resource allocation schemes that benefit from the adoption of the Software-Defined networking (SDN) paradigm. In radio communications, allocation of resources is tightly connected with interference. In this paper, we revisit the way wireless interference is managed and avoided relying on the SDN paradigm for controlling the network. The SDN approach is exploited to expose the lower layers of the stack (e.g., Physical and Medium Access Control) to the controller and its applications by making system parameters available, such that it is possible to dynamically configure the network in a logically centralized fashion, by means of specifically designed algorithms. The contribution of this work is threefold. First, we show how to adapt the SDN paradigm to mobile networks. Second, we propose the interference graph as an abstraction that can be used to control interference. Last, we formulate a throughput optimization tool that uses the proposed interference graph as an input.

Resource pooling via dynamic spectrum-level slicing across heterogeneous networks

The performance gains from dynamic allocation of radio resources across multiple heterogeneous networks is studied. Through virtualization, the physical radio resources of the heterogeneous networks are first abstracted into a centralized pool of virtual radio resources. A dynamic spectrum-level slicing algorithm to share these radio resources across the different networks is then presented. This algorithm is responsive to changing user load and channel conditions. Simulation results show that for representative user arrival statistics, dynamic allocation of radio resources significantly lowers the percentage of dropped packets. In addition, they reveal that the triggers for dynamic allocation of resources across coexisting virtual networks occur every other time interval under the worst case traffic variation in the system (i.e., traffic varies every time interval). Our results suggest that performance benefits can be had even if dynamic spectrum-level slicing does not happen on time scales similar to that of the local resource schedulers residing in each virtual network.

Dynamic strict fractional frequency reuse for software-defined 5G networks

The surge of mobile data traffic has spurred academia and industries to begin developing 5G networks. 5G is meant to overcome limitations of 4G cellular technology relying on the dominant trend of mobile network densification with the deployment of small cell base stations. To accelerate this process, low complexity and inexpensive remote radio heads (RRHs) are deployed massively and connected to a centralized pool of resources. In this work, we study the problem of inter-cell interference (ICI) which arises in frequency reuse one multi-tier 5G networks. We entrust the management of RRHs to a software-defined network controller and we take advantage of network functions virtualization. Our contributions consist of proposing Dynamic Strict Fractional Frequency Reuse (DSFFR), a method to relieve ICI which dynamically divides the small cell area in a different number of sectors. Furthermore, we formulate a joint scheduling problem composed of two schedulers which operate at different time granularity to transmit downlink packets. Modeling the coverage area with the tool of stochastic geometry and solving with simulations the joint scheduling problem, we are able to show that DSFFR outperforms the static scheme. Performances are addressed in terms of spectral efficiency and packet blocking probability.

Software-defined architecture for mobile cloud in device-to-device communication

Device-to-Device (D2D) communication enables direct communication between nearby user devices using cellular or ad hoc links thereby improving the spectrum utilization, system throughput, and energy efficiency of the network. Exploiting mobile cloud based D2D communication architecture underlying LTE cellular network has a huge importance in reducing the transmission power of the UEs resulting an improved battery life. This paper proposes a novel hybrid D2D communication architecture where a centralized Software-Defined Networking (SDN) controller communicates with the cloud head (CH) in order to reduce the number of LTE communication links thereby improving energy consumption. In addition, UEs can participate and perform operations in multiple clouds simultaneously. The obtained simulation results confirm improved energy efficiency as compared to the legacy LTE network.

SoftPSN: Software-Defined Resource Slicing for Low-Latency Reliable Public Safety Networks

Achieving the low-latency constraints of public safety applications during disaster could be life-saving. In the context of public safety scenarios, in this paper, we propose an efficient radio resource slicing algorithm that enables first responders to deliver their life-saving activities effectively. We used the tool of stochastic geometry to model the base station distribution before and after a disaster. In addition, under this umbrella, we also proposed an example of public safety scenario, ultrareliable low-latency file sharing, via in-band device-to-device (D2D) communication. The example scenario is implemented in NS-3. The simulation results show that radio resource slicing and prioritization of first responders resources can ensure ultrareliable low-latency communication (URLLC) in emergency scenarios.

An OpenAirlnterface based implementation of dynamic spectrum-level slicing across heterogeneous networks

In this demo paper we present a dynamic spectrum-level slicing (DSLS) implementation for heterogeneous networks based on an open source software/hardware platform known as OpenAirInterface. Assuming the network traffic load changes every time interval, we mathematically formulate the DSLS as an optimization problem with the corresponding sets of constraints.

Power saving strategy in advanced metering infrastructure for high-density residential community

Data interaction between power consumers and utilities is one of the distinctive features of smart grid. The smart meter plays a core role in data collection and transmission process, which is also considered as one of the most power consuming devices in the whole architecture of distribution power grid. With the large-scale distribution of smart meters in high-density residential communities and increasing data transmission, power saving of smart meter has recently become an attractive research topic in both academia and industry. In this paper, we propose a novel time sequence scheduling based power saving mechanism for controlling the data transmission between smart meters and a sub-data center located in the secondary substation in distribution grid, via establishing two-mode switch target zones in the local smart grid community. We also explore the relationship between the efficiency of power saving based on the new strategy and the number of divided target zones. Simulation results show high performance gian of 50% power saving rate on average, and applicability of the proposed strategy for data transmission in the smart grid when compared to the conventional power management scheme.