Karkazis Panagiotis

Univercity of West Attica · Department of Informatics and Computer Engineering

The demand for connectivity in this fourth industrial revolution, is growing in an exponential rate. As the Fourth-Generation communication systems are replaced by the Fifth and Sixth-Generation ones, a plethora of fundamental performance issues need to constantly be addressed. Virtual network reliability is one of those main challenges for deployi...

Energy-centric network resource management is becoming increasingly crucial regarding the operational support of next-generation networking ecosystems. To realize consistent power-saving provisions on the physical underlay, we propose a network path enumeration and ordering mechanism by means of path algebra’s formulations. This novel path evaluati...

The satisfaction of the Quality of Service (QoS) levels during an entire service life‐cycle is one of the key targets for Service Providers (SP). To achieve this in an optimal way, it is required to predict the exact amount of the needed physical and virtual resources, for example, CPU and memory usage, for any possible combination of parameters th...

Nowadays, service providers’ (SPs) need for efficient resource utilization solutions is more demanding than ever. The optimal use of the physical and virtual infrastructures guarantees that the waste of resources due to overdesign is minimized while the provided services enjoy the required quality of service levels. However, the prediction of the e...

The optimum utilization of infrastructural resources is a highly desired yet cumbersome task for service providers to achieve. This is because the optimal amount of such resources is a function of various parameters, such as the desired/agreed quality of service (QoS), the service characteristics/profile, workload and service life-cycle. The advent...

Virtualization is commonly accepted as the catalyst that would grant the internet the ability to shed the shackles of legacy technologies and evolve to its future self. In order to make this transformation feasible, unavoidable concurrent radical remodeling of all the involved counterparts is required, particularly in the context of automatically a...

Energy efficiency (EE) constitutes a key target in the deployment of 5G networks, especially due to the increased densification and heterogeneity. In this paper, a Deep Q-Network (DQN) based power control scheme is proposed for improving the system-level EE of two-tier 5G heterogeneous and multi-channel cells. The algorithm aims to maximize the EE...

The provision of high data rate services to mobile users combined with improved quality of experience (i.e., zero latency multimedia content) drives technological evolution towards the design and implementation of fifth generation (5G) broadband wireless networks. To this end, a dynamic network design approach is adopted whereby network topology is...

Communication systems are used not only by voice or file exchange applications, but also by other types of applications due to the coexistence of multiple and different verticals. Each vertical has its own requirements in terms of key performance indicators (KPIs) for their applications. Mapping the verticals KPIs into network quality of service (Q...

As the 5G technologies start to become a reality in telecommunication networks, more services and applications are designed to take advantage of the new features that 5G technology is offering. Additionally, several vertical sectors are using advanced applications in order to improve their performances. One important vertical is the Mission Critica...

With the advent of Software Defined Networking (SDN) and Network Function Virtualization (NFV) technologies, the networking infrastructures are becoming increasingly agile in their attempts to offer the quality of services needed by the users, maximizing the efficiency of infrastructure utilization. This in essence mandates the statistical multiple...

The digitization of manufacturing industry has led to leaner and more efficient production, under the Industry 4.0 concept. Nowadays, datasets collected from shop floor assets and information technology (IT) systems are used in data-driven analytics efforts to support more informed business intelligence decisions. However, these results are current...

5G will not simply be an evolution of mobile broadband networks as its predecessors, but will open the door to unique service capabilities, calling for new business models. In this context, Software Defined Networks (SDN) and Network Function Virtualization (NFV) are technologies that will shape the evolution of the telecom sector with new network...

The Industry 4.0 sector is evolving in a tremendous pace by introducing a set of industrial automation mechanisms tightly coupled with the exploitation of Internet of Things (IoT), 5G and Artificial Intelligence (AI) technologies. By combining such emerging technologies, interconnected sensors, instruments, and other industrial devices are networke...

5G is considered to be the technology that will accommodate the development and management of innovative services with stringent and diverse requirements from end users, calling for new business models from the industry. In this context, the development and efficient management of Network Services (NS) serving specific vertical industries and spann...

Currently, in all augmented reality (AR) or virtual reality (VR) educational experiences, the evolution of the experience (game, exercise or other) and the assessment of the user’s performance are based on her/his (re)actions which are continuously traced/sensed. In this paper, we propose the exploitation of the sensors available in the AR/VR syste...

Billions of embedded processors are being attached to everyday objects and houseware equipment to enhance daily activities and enable smart living. These embedded processors have enough processing capabilities to process sensor data to produce smart insights, and are designed to operate for months without the need of physical interventions. Despite...

This chapter analyses the learning principles governing the learning theories of blended learning, personalized learning, adaptive learning, collaborative assisted learning and game-based learning towards capturing requirements of these theories that can be successfully met and aspects that can be significantly facilitated by technological solution...

As cloud services are becoming increasingly popular, the number of operating data centers is accordingly increasing, together with the need of implementing federated data centers and clouds. In this context, we consider a framework for achieving energy efficiency in federated clouds, by means of continuous monitoring and SLA renegotiation, coupled...

Wireless Sensor Networks (WSN) applications continue to expand and already cover almost all our daily activities improving from security and environmental efficiency to gaming experience. The diverse applications running on top of WSNs have led to the design of an immense number of routing protocols. Few years ago, the IETF standardized the IPv6 ro...

Tele-immersive 3D communications pose significant challenges in networking research and request for efficient construction of overlay networks, to guarantee the efficient delivery. In the last couple of years various overlay construction methods have been subject to many research projects and studies. However, in most cases, the selection of the ov...

During the last decades Intelligent Transportation Systems (ITS) have been attracting the interest of an increasing number of researchers, engineers and entrepreneurs, as well as citizens and civil authorities, since they can contribute towards improving road transport safety and efficiency and ameliorate environmental conditions and life quality....

Nowadays one of the issues hindering the potential of federating cloud-based infrastructures to reach much larger scales is their standard management and monitoring. In particular, this is true in cases where these federated infrastructures provide emerging Future Internet and Smart Cities-oriented services, such as the Internet of Things (IoT), th...

We evaluate a routing metric, called TXPFI, which captures the expected number of frame transmissions needed for successful delivery of data in Wireless Sensor Networks (WSNs) featuring non-fully cooperative nodes and unreliable links. The study, which addresses the exploitation of the TXPFI in routing protocols of distance-vector type, assesses th...

Wireless Sensor Networks (WSNs) often need to operate under strict requirements on energy consumption and be capable of self-adapting to the presence of non-trusted nodes which do not fully cooperate in the packet forwarding operation. In such an environment, the mechanism employed for the calculation of routing paths of minimum cost in terms of th...

During the last decades Intelligent Transportation Systems ITS have been attracting the interest of an increasing number of researchers, engineers and entrepreneurs, as well as citizens and civil authorities, since they can contribute towards improving road transport safety and efficiency and ameliorate environmental conditions and life quality. Em...

The wide deployment of Wireless Sensor Networks along with the proliferation of applications that use WSN-generated data has led to the design of WSN architectures and systems that support multiple applications over the same WSN infrastructure. Different Quality of Service requirements imposed by different applications impose the use of appropriate...

Future Internet is expected to incorporate large volumes of diverse sensing devices organized in Wireless Sensor Networks (WSNs) and reacting upon real-world phenomena. Security has attracted significant research efforts converging to trust management systems, in which nodes trust establishment is based on both direct observations and recommendatio...

The use of Wireless Sensor Networks (WSN) in a wide variety of application domains has been intensively pursued lately while Future Internet designers consider WSN as a network architecture paradigm that provides abundant real-life real-time information which can be exploited to enhance the user experience. The wealth of applications running on WSN...

The networking of sensing devices has fuelled the development of a great variety of applications which lead to the wide deployment of Wireless Sensor Networks. Nowadays, as the sensor population becomes constantly denser, the exploitation of the vastly installed WSN infrastructure to feed with data additional applications is pursued. The research c...

The integration of Wireless Sensor Networks (WSNs) in the Future Internet has opened new opportunities for novel applications that meet the needs of modern societies. Virtualisation of the available resources and the services offered by WSNs enables their efficient sharing between diverse applications reducing costs. Responding to this challenge, t...

Wireless sensor networks are vulnerable to a wide set of security attacks, including those targeting the routing protocol functionality. The applicability of legacy security solutions is disputable (if not infeasible), due to severe restrictions in node and network resources. Although confidentiality, integrity and authentication measures assist in...

The usability of wireless sensor networks in modern applications requires the fulfillment of dynamic Quality of Service (QoS) requirements that can only be met in a reactive manner by the introduction of composite routing metrics, capturing several distinct network characteristics. However, combining routing metrics is neither a trivial nor an arbi...

As the applications of wireless sensor networks proliferate, the efficiency in supporting large sensor networks and offering security guarantees becomes an important requirement in the design of the relevant networking protocols. Geographical routing has been proven to efficiently cope with large network dimensions while trust management schemes ha...

Wireless sensor networks offer inexpensive solutions in a wide variety of applications ranging from health, home, roads and public area monitoring to industry and aircraft control. As sensors proliferate, scalable communication protocols with low implementation requirements are pursued. Another key issue for the wider deployment of these solutions...

The diversity of applications that current and emerging Wireless Sensor Networks (WSNs) are called to support imposes different requirements on the underlying network with respect to delay and loss, while at the same time the WSN imposes its own intricacies. The satisfaction of these requirements highly depends on the metric upon which the forwardi...

Recently, Routing Protocol for Low Power and Lossy Networks (RPL) has been proposed by IETF ROLL WG in order to cope with Low Power and Lossy Networks (LLN) requirements implied by different application domains. In this paper, we present RPL modeling in J-Sim simulation environment, providing a complete simulation framework for performance evaluati...

As the applications of Wireless Sensor Networks proliferate, security issues raised in this uncontrolled, self- organised systems comprising a large number of nodes with very low processing, buffering and communication capabilities become mandatory as they need to cooperate with each other, even for routing data messages to the desired destination....

Security in sensor networks is one of the most relevant research topics in resource constrained wireless devices and networks. Several attacks can be suffered in ad hoc and wireless sensor networks (WSN), which are highly susceptible to attacks, due to the limited resources of the nodes. In this paper, we propose innovative and lightweight localiza...

Wireless Sensor Networks are gaining popularity due to the fact that they offer low-cost solutions for a variety of application areas. However, these networks are highly susceptible to attacks, due to both the open and distributed nature of the network, as well as the limited resources of the nodes, which dictate the implementation of sophisticated...

Wireless Sensor Networks are gaining popularity due to the fact that they offer low-cost solutions for a variety of application domains. However, these networks are highly susceptible to attacks, due to both the open and distributed nature of the network, as well as the limited resources of the nodes, which dictate the implementation of sophisticat...

Wireless Sensor Networks are becoming more and more popular and offer a wide set of solutions invading our life. As the research community is working towards integrating them in the so-called “Internet of Things”, the capability to reconfigure them provides an unprecedented flexibility allowing for the flexible use of all available resources of dif...

The domain of Wireless Sensor Networks (WSNs) applications is increasing widely over the last few years.As this new type of networking is characterized by severely constrained node resources, limited networkresources and the requirement to operate in an ad hoc manner, implementing security functionality toprotect against adversary nodes becomes a c...

Wireless Sensor Networks (WSN) are vulnerable to a wide set of attacks which threaten the network operation. Although communication and security technologies for computer networks have reached a mature stage, their applicability in WSNs is disputable due to their infrastructure-less operation and the limited node and network resources. Focusing on...

Efficient defense against security attacks is a challenging task in the wireless sensor network environment. Although significant research effort has been spend on the design of trust models to detect malicious nodes based on direct and indirect evidence, this comes at the cost of additional energy consumption. The situation is further aggravated a...

A lot of effort has been spent in securing the routing procedure in wireless sensor network (WSNs) since this is accomplished in a cooperative way and is vital for the communication of the sensors with the base station which collects the sensed data. The communication over wireless links in combination with the ad hoc organization introduces vulner...

Security has been recognised as a key issue for the expansion of wireless sensor network applications. To defend against the wide set of security attacks, legacy security solutions are not applicable due to the very limited memory and processing resources of the sensor nodes as well as due to the reason that sensor networks are required to operate...

Efficient defense against security attacks is a challenging task in the wireless sensor network environment. Due to their infrastructure-less operation and the limited node and network resources, the applicability of legacy security solutions is disputable. The situation is further aggravated as the next generation wireless sensor network become la...