Department Publications

This paper addresses the urgent question of how emerging telecommunication networks, particularly beyond 5G and 6G networks, can be designed and governed to support climate action while limiting their own environmental footprint. We provide a comprehensive and cross-disciplinary analysis of the role of telecommunications in climate change adaptation, mitigation, and sectoral decarbonization, going beyond existing studies that typically focus on isolated technologies or single application domains. We review international climate and telecom policy frameworks, evaluate emerging 5G/6G capabilities, and analyze regulatory pathways for green networks to assess how next-generation connectivity, AI-based energy optimization, remote monitoring systems, and renewable integration can reduce emissions and enhance network resilience. Our findings organize these developments into a novel three-pillar …

This work presents the development of an opensource standalone (SA) 5G testbed with end-to-end slicing, using open-source software on commercial off-the-shelf (COTS) hardware and software-defined radio (SDR). Key contributions include customized slice configurations in the 5G Core Network (5GC) and dedicated static resource allocation in the radio access network (RAN). The testbed is validated through slice isolation tests. Its utility is then demonstrated via a warehouse application featuring Automated Guided Vehicles (AGVs) on one slice and environmental sensors & actuators on another. Critical AGV response times are evaluated under mixed traffic conditions, showing robust slice isolation and superior performance over baseline networks. The testbed offers a scalable, cost-effective platform for 5G education, research, and application testing. It also highlights the transformative potential of such open …

The deployment of 5G networks using open-source software platforms on commodity hardware and software defined radios (SDRs) has become increasingly important for both research and prototyping. Most work is constrained to a single platform such as OpenAirInterface (OAI), inhibiting the potential for cross-platform trade-offs. This paper presents Open5GFusion, a heterogeneous 5G Standalone (SA) testbed that combines OAI, srsRAN, and Open5GS to enable flexible experimentation with different core network (CN) and radio access network (RAN) alternatives and to exploit the strengths of each. A graphical user interface (GUI) simplifies deployment management and monitoring across different CN/RAN combinations. The testbed leverages commercial off-the-shelf (COTS) hardware with USRP B210 and N310 SDRs, allowing real-time evaluation of throughput, latency, modulation schemes, network slicing …

It is envisioned that 6G networks will be supported by key architectural principles, including intelligence, decentralization, interoperability, and digitalization. With the advances in artificial intelligence (AI) and machine learning (ML), embedding intelligence into the foundation of wireless communication systems is recognized as essential for 6G and beyond. Existing radio access network (RAN) architectures struggle to meet the ever growing demands for flexibility, automation, and adaptability required to build self-evolving and autonomous wireless networks. In this context, this paper explores the transition towards AI-driven RAN (AI-RAN) by developing a novel AI-RAN framework whose performance is evaluated through a practical scenario focused on intelligent orchestration and resource optimization. Besides, the paper reviews the evolution of RAN architectures and sheds light on key enablers of AI-RAN including digital twins (DTs), intelligent reflecting surfaces (IRSs), large generative AI (GenAI) models, and blockchain (BC). Furthermore, it discusses the deployment challenges of AI-RAN, including technical and regulatory perspectives, and outlines future research directions incorporating technologies such as integrated sensing and communication (ISAC) and agentic AI.

The emergence of 5G technology has transformed network architecture, with network slicing technology standing out as a crucial feature for managing diverse and demanding applications. This innovative technology allows the creation of multiple virtual networks within a single physical infrastructure, each dedicated to specific needs such as latency, bandwidth, and reliability. These capabilities are vital for supporting services like enhanced mobile broadband, ultra-reliable low-latency communications, and massive machine-type communications. Predicting the optimal configuration of network slices is challenging due to the complex and dynamic nature of 5G environments. While traditional methods often lack the necessary accuracy, machine learning models have shown promise in addressing this challenge. However, the adoption of these models introduces the challenge of interpretability, as understanding how …

The energy consumption of telecommunication networks has been rising steadily due to the expansion of networks, power-hungry equipment and ever-increasing consumer demand. This contributes significantly to the world’s carbon footprint and greenhouse emissions. In particular, radio access networks (RANs) have been identified to have a larger contribution to the energy consumption of telecommunication networks, and a thorough evaluation is required to understand the avenues for energy reduction. In light of that, this study discusses various strategies to lower RAN power usage to minimize telecommunication’s environmental effect. Furthermore, a two-pronged strategy that combines dynamic operation management of base stations (BSs) and renewable energy integration is introduced to reduce the environmental impacts of RANs. With this hybrid strategy energy consumption and carbon footprint may be …

The imminent emergence of quantum computers poses unprecedented challenges to the current cryptographic standards that secure vital digital communications and data worldwide. This paper addresses the vulnerabilities of existing cryptographic systems susceptible to quantum-based attacks and emphasizes a dedicated transition plan to post-quantum cryptography (PQC). We first examine the current state of cryptographic practices, highlight the quantum threat, and present the framework and need for PQC. In addition, a comprehensive strategy is presented that encompasses the identification, protection, detection, response, and recovery phases and integrates PQC into existing security infrastructures, specifically the Cybersecurity Framework Version 2.0 of the National Institute of Standards and Technology (NIST). Methods and technologies discussed include the development of robust PQC algorithms, tools …

The upcoming Sixth Generation (6G) networks aim for fully automated, intelligent network functionalities and services. Therefore, Machine Learning (ML) is essential for these networks. Given stringent privacy regulations, future network architectures should use privacy-preserved ML for their applications and services. Federated Learning (FL) is expected to play an important role as a popular approach for distributed ML, as it protects privacy by design. However, many practical challenges exist before FL can be fully utilized as a key technology for these future networks. We consider the vision of a 6G layered architecture to evaluate the applicability of FL-based distributed intelligence. In this paper, we highlight the benefits of using FL for 6G and the main challenges and issues involved. We also discuss the existing solutions and the possible future directions that should be taken toward more robust and trustworthy FL …

The radio spectrum is a scarce and vital resource. Every country in the world has sovereign control over its spectrum. Demand for the spectrum in terms of mobile communication-related applications is increasing continuously. As a result, Mobile network operators (MNO) are keen to acquire additional spectrum bands to deploy in mobile networks. 5G technology, as the latest generation of mobile telephony with many advanced features has opened many doors to other industries such as virtual reality, the Internet of Things(IoT), smart cities, smart health care, etc. and demand for them is trending. As a result of its technological advancements and the economic benefits of 5th generation technology (5G), network operators are keen to migrate to 5G. Due to the excessive demand for the spectrum, the true value of the spectrum has gone up drastically. Therefore, understanding the true value of spectrum has become a …

Metaverse is the latest technological hype in the modern world due to its potential for revolutionizing the digital visual perspective. With the COVID-19 pandemic, most industries have moved towards digitization, and the metaverse is identified as one of the most promising platforms for such a transition, as it provides a three-dimensional (3D) immersive experience for the users. Currently, most digital service providers and organizations are actively working on metaverse- based applications. In addition, there has been a rapid increase on research work involving metaverse realization. Launching a large scale metaverse in the real world is a challenging task. However, fifth-generation (5G) and beyond 5G (B5G) technologies are envisioned to improve the feasibility of pragmatic deployments. Although, there are several conceptual designs available, actual adaptations of the concepts are still limited. This survey …

Prioritization of data streams in cellular vehicle-to-everything (C-V2X) may lead to unfavorable packet delays in low-priority streams. This paper studies allocating multiple candidate single-subframe resources (CSRs) per vehicle as a solution. It proposes a methodology to determine the number of CSRs for each vehicle based on the total number of neighboring vehicles, and to assign the multiple data streams among them for simultaneous transmission. The numerical results highlight the achievable delay gains of the proposed approach, and its negligible impact on packet collisions.

Network slicing enables the creation of multiple logical independent networks on physical networking infrastructure. Network slice deployment in a Fifth Generation (5G) mobile network can be classified as vertical and horizontal slicing. The paper compares the performance of the two slicing methods through solving two convex optimization problems, considering several smart hospital scenarios that differ from each other based on their medical speciality. The results are used to draw insights on the most appropriate slicing approach for each setup.

Mobile users may experience frequent service outages or poor quality of service in rural areas due to the scarcity of base stations in the proximity. Therefore, a cost effective and flexible solution is introduced in this paper with unmanned aerial vehicles (UAVs) and terrestrial base stations (TBSs), coexisting under a stochastic network with the combination of millimeter waves and non-orthogonal access (NOMA) techniques. This is achieved by deploying both the UAVs (millimeter wave frequencies) and TBSs (sub-6 GHz frequencies) in the same system, and selecting the transmitter based on a user association scheme. The maximum signal-to-interference-plus-noise ratio (SINR) and the closest transmitter user association schemes are compared using extensive simulations to identify the most suitable scheme in terms of the outage probability and the achievable downlink rate. The results show that the closest …

Supporting parallel multi-priority data streams is vital for maintaining the quality of service (QoS) in vehicle-to-everything (V2X) communication. Hence, the European telecommunications standard institute (ETSI) has defined four packet types, with varying priority levels, to be used as broadcast packets in such communication. This paper studies the medium access control (MAC) layer performance of IEEE 802.11p and cellular-V2X (C-V2X) Mode 4 using discrete-time Markov chain (DTMC) based models, while considering parallel multi-priority data streams. The overall model consists of four queue models with their respective traffic generators, which are appropriately linked with the DTMCs modeling the MAC layer operations of IEEE 802.11p and C-V2X Mode 4. Closed-form solutions for the steady-state probabilities of the models are obtained, which are then utilized to derive expressions for key performance …

Vehicle-to-vehicle (V2V) communication plays a pivotal role in intelligent transport systems (ITS) with cellular-vehicle to everything (C-V2X) and IEEE 802.11p being the two competing enabling technologies. This paper presents multi-dimensional discrete-time Markov chain (DTMC) based models to study the medium access control (MAC) layer performance of the IEEE 802.11p standard and C-V2X Mode 4, considering periodic cooperative awareness messages (CAMs) and event-driven decentralized environmental notification messages (DENMs). Closed-form solutions for the steady-state probabilities of the models are obtained, which are then utilized to derive expressions for several key performance metrics. Numerical results are provided to draw insights on the performance. In particular, a performance comparison between IEEE 802.11p and C-V2X Mode 4 in terms of the average delay, the collision …

Network softwarization enables the novel concept of Local 5G Operator (L5GO) networks, for deploying localized 5G solutions to serve case and location specific communication needs. This paper proposes a L5GO network architecture for delay critical future telehealth services, considering two use cases on augmented reality assisted and robotic aided surgery. The paper compares the latency performance of the proposed L5GO architecture with a traditional legacy network and a network equipped with Multi-access Edge Computing (MEC). The results highlight the unique advantages of utilizing an L5GO to cater the communication needs of delay critical telehealth, compared to a traditional network.

A variety of applications and forwarding protocols have been proposed for opportunistic networks (OppNets) in the literature. However, the methodology of evaluation, testing and comparing these forwarding protocols are not standardized yet, which leads to large levels of ambiguity in performance evaluation studies. Performance results depend largely on the evaluation environment, and on the used parameters and models. More comparability in evaluation scenarios and methodologies would largely improve also the availability of protocols and the repeatability of studies, and thus would accelerate the development of this research topic. In this survey paper, we focus our attention on how various OppNets data forwarding protocols are evaluated rather than what they actually achieve. We explore the models, parameters and the evaluation environments and make observations about their scalability, realism and comparability. Finally, we deduce some best practices on how to achieve the largest impact of future evaluation studies of OppNets data dissemination/forwarding protocols.

Telecommunication sector is one of the technologically advanced sectors, globally. The mobile device market is always growing and it is very competitive. Counterfeit and substandard devices are collectively known as black market devices. Availability of black market and stolen mobile devices is a global issue. When buying a mobile device, most of the people focus on cost, brand and model. The important factors that represent the standard of mobile devices such as validity of International Mobile Equipment Identity (IMEI) and the Specific Absorption Rate (SAR) value are neglected. It is important to adhere to a proper policy framework and introduce systems such as Equipment Identity Registers (EIRs) to minimize the usage of black market and stolen mobile communication devices. Mobile device blocking and regulation have become difficult tasks due to the unavailability of proper systems and policies. This has …

This paper proposes a spectrum selection scheme and a transmit power minimization scheme for a device-to-device (D2D) network cross-laid with a cloud radio access network (CRAN). The D2D communications are allowed as an overlay to the CRAN as well as in the unlicensed industrial, scientific and medical radio (ISM) band. A link distance based scheme is proposed and closed-form approximations are derived for the link distance thresholds to select the operating band of the D2D users. Furthermore, analytical expressions are derived to calculate the minimum required transmit power to achieve a guaranteed level of quality of service in each operating band. The results demonstrate that the proposed scheme achieves nearly 50% power saving compared to a monolithic (purely overlay or purely ISM band) D2D network.

A novel content caching strategy is proposed for a cache enabled device-to-device (D2D) network where the user devices are allowed to communicate using millimeter wave (mmWave) D2D links (> 6GHz) as well as conventional sub 6 GHz cellular links. The proposed content placement strategy maximizes the successful content delivery probability of a line of sight D2D link. Furthermore, a heuristic algorithm is proposed for efficient content delivery. The overall scheme improves the successful traffic offloading gain of the network compared to conventional cache-hit maximizing content placement and delivery strategies. Significant energy efficiency improvements can also be achieved in ultra-dense networks.

This paper presents an analytical framework to investigate the performance of full duplex (FD) device-to-device (D2D) networks where devices in a cluster are capable of caching popular content. Assuming spatially randomly distributed D2D users in the cluster where the users request for content according to the Zipf distribution, analytical expressions are derived for the device communication probability, coverage probability, cluster average spectral efficiency, and content average download latency of the system. The system performance metrics are derived for the three device operating modes of FD only mode, half duplex (HD) only mode, and mixed FD/HD mode. Numerical results show that the mixed FD/HD mode is the most appropriate communication mode for cache enabled FD D2D networks to achieve the highest cluster average spectral efficiency and low content average download latency.

This paper proposes and analyzes a distance-based duplex mode switching scheme for maximizing the average throughput of a cellular network and its underlay device-to-device (D2D) network. For each duplex mode of the cellular network, a node distance based duplex mode selection scheme is proposed to maximize the throughput of the D2D network. The proposed duplex mode selection scheme provides average throughput improvements in the range of 10%-200% for the D2D network compared to the always half-duplex and always full-duplex communications for high D2D user scatter variances.

A throughput analysis is conducted for a large scale peer-to-peer wireless network whose devices are capable of operating in both full- and half-duplex modes, using the tools of stochastic geometry. Each device selects its operating duplex mode based on the distance to its partner node. In both duplex modes, the energy consumption and the hardware configurations of the nodes are made equivalent for fair comparisons between full-duplex and half-duplex operations. Using the results of the analysis, an approach is proposed to determine a distance threshold value for duplex mode selection, and the proposed distance threshold can be computed offline. It is found that the throughput performance of the hybrid full-/half-duplex network generated with the proposed distance threshold based duplex mode selection technique outperforms both the pure half-duplex and pure full-duplex network settings for most …