A5081897835- Advanced MIMO Systems Optimization
- Software-Defined Networks and 5G
- IoT and Edge/Fog Computing
- Advanced Wireless Network Optimization
- Cooperative Communication and Network Coding
- IoT Networks and Protocols
- Image and Video Quality Assessment
- Wireless Communication Networks Research
- Energy Harvesting in Wireless Networks
- Advanced Wireless Communication Technologies
- Multimedia Communication and Technology
- Advanced Optical Network Technologies
- Network Traffic and Congestion Control
- Telecommunications and Broadcasting Technologies
- Cognitive Radio Networks and Spectrum Sensing
- Wireless Networks and Protocols
- Wireless Body Area Networks
- PAPR reduction in OFDM
- Caching and Content Delivery
- Advanced Wireless Communication Techniques
- Video Coding and Compression Technologies
- Economic and Industrial Development
- IPv6, Mobility, Handover, Networks, Security
- Software System Performance and Reliability
- Power Line Communications and Noise
National and Kapodistrian University of Athens
2015-2024
Athens Information Technology
2022
Mobics (Greece)
2018-2019
Athens State University
2008
Telecom operators have recently faced the need for a radical shift from technical quality requirements to customer experience guarantees. This trend has emerged due constantly increasing amount of mobile devices and applications explosion overall traffic demand, forming new era: "the rise consumer". New terms been coined in order quantify, manage, improve experienced user quality, with QoE being most dominant one. However, always an afterthought network providers, thus numerous research...
The Internet of Things (IoT) ecosystem emerges rapidly and paves the way towards collecting huge amounts data that can feed innovative information-based systems. connectivity infrastructure will support IoT encompasses deployments define so-called Low-Power Wide Area Networks (LPWANs). LPWANs are an attractive solution for service provisioning, since they incorporate energy-efficient cost-effective technologies. In this context, a comprehensive study is provided to assist in currently...
The Long Term Evolution (LTE) system, and especially its current release, LTE-Advanced, is considered as the next step in mobile broadband networks. Two of main challenges faced by LTE system are: i) to offer ubiquitous highly reliable wireless services, ii) efficiently utilize assigned spectrum portion. A promising approach towards this direction allow establishment direct device-to-device (D2D) communications spectrum. In paper, we study how traffic load between users located same cell...
The emergence of 5G enables a broad set diversified and heterogeneous services with complex potentially conflicting demands. For networks to be able satisfy those needs, flexible, adaptable, programmable architecture based on network slicing is being proposed. A softwarization cloudification the communications required, where functions (NFs) are transformed from programs running dedicated hardware platforms over shared pool computational communication resources. This architectural framework...
This paper describes the pathway towards realisation of a 5G Facility that will allow validation major Key Performance Indicators (KPIs). It reflects approach 5GENESIS consortium adopt in this direction. More precisely, it key design principles such as well targeted use cases for KPIs validation. The adopted includes common implementation blueprint be instantiated five Platforms distributed across Europe. To maximise diversity and efficiency Facility, complementary performance objectives...
The existing mobile network infrastructure is currently optimized to support the Narrow-Band Internet of Things (NB-IoT), which meant provide numerous services in poor coverage areas, with ultra-low power consumption. question that arises whether (and what extent) NB-IoT can meet requirement for massive Machine Type Communications (mMTC) 5G era. In view this, we study enhancement NB-IoT. We describe subframe structure various physical channels and explain repetition mechanism used downlink...
Vertical markets and industries are addressing a large diversity of heterogeneous services, use cases, applications in 5G. It is currently common understanding that for networks to be able satisfy those needs, flexible, adaptable, programmable architecture based on network slicing required. Moreover, softwarization cloudification the communications already happening, where functions (NFs) transformed from monolithic pieces equipment programs running over shared pool computational...
5G communications are expected to adopt a user-centric service provisioning approach, transforming the current Quality of Service (QoS) networking paradigm Experience (QoE) platform. Towards this direction, design QoE quantification methods is vast necessity, prior QoE-driven service/network management techniques and proposal QoE-aware customer experience charging policies. Contributing effort, in paper we provide comprehensive overview inventory currently available estimation approaches...
In this paper, we define a flexible, adaptable, and programmable architecture for 5G mobile networks, taking into consideration the requirements, KPIs, current gaps in literature, based on three design fundamentals: (i) split of user control plane, (ii) service-based within core network (in line with recent industry standard consensus), (iii) fully flexible support E2E slicing via per-domain cross-domain optimisation, devising inter-slice management functions, refining behavioural models...
The high heterogeneity of 5G use cases requires the extension traditional per-component testing procedures provided by certification organizations, in order to devise and incorporate methodologies that cover requirements from vertical applications services. In this paper, we introduce an experimentation methodology is defined context 5GENESIS project, which aims at enabling both network components validation E2E KPIs. most important contributions are its modularity flexibility, as well...
This paper provides a brief overview and vision for introducing Quality of Experience (QoE) function on-demand services or premium users, based-on Software-Defined Networking (SDN). The proposed "QoE-service" can take advantage the SDN global resource view complementary QoE metrics to assure desired performance OTT applications by adopting traffic management mechanisms. introduces QoE-Service concept architecture it presents set use cases that demonstrate its suitability applicability Long...
The 5th Generation (5G) of mobile networks brings the concept openness to vertical industries, by enabling new levels programmability in network core and edge domains. Openness is enabled through APIs it creates field for developing 5G-enabled applications, i.e., applications that can interact with underlay network. In this context, a framework envisaged, major objective support development as well as, their testing, prior interacting commercial networks. Implementation directions proposed...
The effective support of 5G-Internet Things (IoT) requires cellular service in deep coverage areas while providing long battery life for IoT devices that perform infrequent small data transmission toward the base station. Relaying is a promising solution to extend at same time meeting requirements devices. Considering this, we analyze suitability layer-3 relaying over 3GPP Release 16 NR-PC5 interface massive applications. More precisely, study unicast connection establishment mechanism NR...
Device-to-Device (D2D) communication has been recently devised as a new paradigm that boosts spectrum reuse inside cell, leading to enhanced quality of service and user experience. The design proper D2D resource allocation schemes, which constitute the enablers towards this direction, is an open challenge. In paper, we propose allocator based on Ant Colony Optimization (ACO) theory. ACO exploited identifying interference isolated links can safely share same resources, consulting graph...
Video streaming provided by Over-The-Top (OTT) service providers through a cellular network is common usage scenario for many people today. While video will work reasonably well in stationary scenario, several issues arise mobile users. For instance, travelling short areas without coverage, such as an automobile tunnel, often result quality degradation or stalling. To combat this, this paper provides analytical investigation of the problem it experienced users and suggests context-aware HTTP...
The technology of Narrow Band Internet Things (NB-IoT) is expected to contribute towards the support massive Machine Type Communications (mMTC), i.e., one fundamental performance objectives 5G networks. However, that call for massiveness, requests a thorough revisit on NB-IoT access procedure. Considering this, procedure analysed under different network densities and various combinations related configuration parameters. analysis led useful reference table with 3GPP compliant configurations...
The 3GPP Common API Framework (CAPIF) has been standardized to guarantee a unique reference model for API-based service provisioning in systems. great potential of such framework is currently revealed due the need interaction between vertical industries and mobile networks. Towards realizing above-mentioned interaction, we describe key functional aspects CAPIF by focusing on related entities APIs. In addition, implemented Core Function, i.e., main entity CAPIF, as an effort set basis...
The 3GPP Common API Framework (CAPIF) has been an integral part of the SA6 specifications. It defined to facilitate network core exposure, towards new application enablers various vertical industries (including, Unmanned aerial systems, Edge data networks, Factories future, and Vehicular communication systems). Beyond its initial target, we believe that CAPIF can be used as a key standardized API-management framework for secure interoperable interaction among any providers consumers. In this...
Device-to-Device (D2D) communications are currently attracting high interest from industry and academia, targeting at new commercial public safety proximity services (ProSe). A major challenge under consideration is the device discovery problem, i.e., problem of meeting communication peers in time, frequency space. In line with current standardization efforts 3rd Generation Partnership Project (3GPP), we propose a centrally controlled scheme which consists an application layer procedure set...