Donatos Stavropoulos

Network Store: Exploring Slicing in Future 5G Networks

In this paper, we provide a revolutionary vision of 5G networks, in which SDN technologies are used for the programmability of the wireless network, and where a NFV-ready network store is provided to Mobile Network Operators (MNO), Enterprises, and Over-The-Top (OTT) third parties. The proposed network serves as a digital distribution platform of programmable Virtualized Network Functions (VNFs) that enables 5G application use-cases. Currently existing application stores, such as Apples App Store for iOS applications, Googles Play Store for Android, or Ubuntus Software Center, deliver applications to user specific software platforms. Our vision is to provide a digital marketplace, gathering 5G enabling Network Applications and Network Functions, written to run on top of commodity cloud infrastructures, connected to remote radio heads (RRH). The 5G Network Store will be the same to the network provider as the application store is currently to a software platform.

Demonstration of a Vehicle-to-Infrastructure (V2I) Communication Network Featuring Heterogeneous Sensors and Delay Tolerant Network Capabilities

The development of applications based over vehicular networks, such as road safety, environmental information etc. require a complete testbed platform for research and evaluation. Such a platform will be provided by NITOS[1] testbed, that will include nodes mounted on cars and fixed nodes of the testbed operating as road side units (RSU). Besides the wireless infrastructure, there will be several sensors regarding the environmental conditions and the vehicle. These will gather measurements about air conditions and GPS data such as position and speed and will be collected in a central database, where the experimenter will be able to depict them in a Google map.

NITOS BikesNet: Enabling Mobile Sensing Experiments through the OMF Framework in a City-Wide Environment

In this paper we present the NITOS Bikes Net platform, a city-scale mobile sensing infrastructure that relies on bicycles of volunteer users. NITOS Bikes Net employs a custom-built embedded node that can be equipped with different types of sensors, and which can be easily mounted on a bicycle in order to opportunistically collect environmental and WiFi measurements in different parts of the city. Experimenters can remotely reserve and control the sensor nodes on bicycles as well as collect/visualize their measurements via the OMF/OML framework, which was extended in order to handle the intermittent connectivity and disconnected operation of the mobile nodes. We also provide a performance analysis of our node prototype in terms of sensing latency, end-to-end data transmission capability and power consumption, and report on a first experiment that was performed using NITOS Bikes Net in the city of Volos, Greece.

Enabling mobile sensing through a DTN framework

Participatory Sensing is the concept of distributed data collection by self-selected participants. By exploiting latest technologys smart devices, a large number of valuable information can be collected through embedded sensors and also be uploaded using provided services. Environmental measurements such as temperature or pollution, while also real-time data considering products information (i.e. prices, availability, offers), can be provided through such a framework. In this paper we present the NITOS mobile framework for data collection, that exploits vehicles moving around in a city. The proposed framework consists of low-sized wireless devices mounted on volunteers vehicles, as well as of static deployed Road Side Units (RSUs) providing the backbone connection for data acquisition. The extracted measurements concern air temperature and humidity plus the available WiFi networks operating in each area.

Building virtual 802.11 testbeds towards open 5G experimentation

Together with recent advancements in Radio Access Network (RAN) technologies, Wi-Fi is expected to be at the center of research on the subject of ubiquitous wireless connectivity, towards building the new 5G ecosystem. Nevertheless, the necessary testbed infrastructure to support large scale experimentally driven research seems to be missing. In this work we present the design and implementation of a novel Virtual Wi-Fi Testbed. We present how a traditional Wireless Testbed can support hundreds of virtual Wi-Fi nodes that are open to experimenters. We discuss the design and implementation of the virtualization tools. We demonstrate the accuracy and the overhead analysis of the approach in the face of actual testbed conditions. Implementation experience is also reported on the benefits of using the proposed virtualization approach for a simple association algorithm.

Enabling experimentation in mobile sensing scenarios through 4G networks: The NITOS approach

Wireless technologies have evolved rapidly over the past years, directly affecting our everyday living with the wide penetration of smart mobile devices. As such, the research community has placed major efforts in shaping and forming the future wireless technologies for enhanced end-user experience. Nevertheless, protocols and algorithms over wireless networks are better evaluated in real world scenarios, where simulations and complex theoretical models fail to characterize and emulate their behavior. Networking experimental facilities (testbeds) fill this gap by allowing experimental network measurements to serve as a basis for extracting valuable findings. In this paper, we present the extensions to the NITOS testbed for supporting experimentation in mobile sensing scenarios, by employing smartphones in vehicular environments, communicating using WiFi and 4G networks. We emphasize on the ease of configuration, execution and reproducibility of these experiments, leveraging the hardware and software tools provided by the NITOS testbed.