Pantelis A. Frangoudis's research while affiliated with TU Wien and other places

Publications (83)

Preprint
Full-text available
The trend towards the cloudification of the 3GPP LTE mobile network architecture and the emergence of federated cloud infrastructures call for alternative service delivery strategies for improved user experience and efficient resource utilization. We propose Follow-Me Cloud (FMC), a design tailored to this environment, but with a broader applicabil...
Preprint
Full-text available
Through network slicing, different requirements of different applications and services can be met. These requirements can be in terms of latency, bandwidth, mobility support, defining service area, as well as security. Through fine and dynamic tuning of network slices, services can have their delivery platforms constantly customized according to th...
Preprint
Full-text available
We present an architecture for the provision of video Content Delivery Network (CDN) functionality as a service over a multi-domain cloud. We introduce the concept of a CDN slice, that is, a CDN service instance which is created upon a content provider's request, is autonomously managed, and spans multiple potentially heterogeneous edge cloud infra...
Article
Vertical farming is the practice of growing crops vertically to increase total yield for a given space and is one approach towards sustainable food production. Concerns related with its operational costs, and the need to optimize plant growth parameters in a controlled environment call for advanced use of IoT technologies to develop low-cost mechan...
Chapter
Contemporary component-based systems often manifest themselves as service-based architectures, where a central activity is management of their software updates. However, stringent security constraints in mission-critical settings often impose compulsory network isolation among systems, also known as air-gap; a prevalent choice in different sectors...
Article
Full-text available
Fog computing enables the execution of IoT applications on compute nodes which reside both in the cloud and at the edge of the network. To achieve this, most fog computing systems route the IoT data on a path which starts at the data source, and goes through various edge and cloud nodes. Each node on this path may accept the data if there are avail...
Article
One of the main challenges when it comes to deploying Network Slices is slicing the Radio Access Network (RAN). Indeed, managing RAN resources and sharing them among network slices is an increasingly difficult task, which needs to be properly designed. The goal is to improve network performance and introduce flexibility and greater utilization of n...
Article
Full-text available
Complex distributed systems such as the ones induced by Internet of Things (IoT) deployments, are expected to operate in compliance to their requirements. This can be checked by inspecting events flowing throughout the system, typically originating from end-devices and reflecting arbitrary actions, state changes or sensing. This paper presents a se...
Article
The plethora of available IoT connectivity technologies makes selection of the most suitable and affordable offering challenging for IoT service providers. This is a typical problem when considering deployments over Low-Power Wide-Area Networks (LPWAN). Each technology has different implications as to how edge, fog, and cloud resources can be utili...
Article
We present an architecture for the provision of video Content Delivery Network (CDN) functionality as a service over a multi-domain cloud. We introduce the concept of a CDN slice, that is, a CDN service instance which is created upon a content provider's request, is autonomously managed, and spans multiple, potentially heterogeneous, edge cloud inf...
Article
In the near future, 5G-connected vehicles will be able to exchange messages with each other, with the roadside infrastructure, with back-end servers, and with the Internet. They will do so with reduced latency, increased reliability, and large throughput under high mobility and user density. Different services with different requirements, such as A...
Conference Paper
Channel quality feedback is crucial for the operationof 4G and 5G radio networks, as it allows to control UserEquipment (UE) connectivity, transmission scheduling, and themodulation and rate of the data transmitted over the wirelesslink. However, when such feedback is frequent and the number ofUEs in a cell is large, the channel may be overloaded b...
Article
The Internet of Things (IoT) undergoes a rapid transformation this last decade, thanks to the appearance of low-power wide area network technologies, such as LoRa/LoRaWAN, SigFox, and narrowband IoT, which allow reducing the deployment cost of sensors and other IoT devices. Many emerging services such as smart city, Industry 4.0, and autonomous dri...
Article
Multi-access Edge Computing (MEC) and Network Slicing are two key enablers for 5G, particularly to empower low-latency services, known as Ultra-Reliable Low Latency Communications (URLLC). However, MEC and Network Slicing are evolving in parallel, and are being defined by two different standardization bodies, ETSI and 3GPP, which limits their integ...
Article
Through network slicing, different requirements of different applications and services can be met. These requirements can be in terms of latency, bandwidth, mobility support, defining service area, and security. Through fine and dynamic tuning of network slices, services can have their delivery platforms constantly customized according to their cha...
Article
Multi-access edge computing (MEC) comes with the promise of enabling low-latency applications and of reducing core network load by offloading traffic to edge service instances. Recent standardization efforts, among which the ETSI MEC, have brought about detailed architectures for the MEC. Leveraging the ETSI model, in this paper we first present a...
Article
With advent of 5G, the classical mobile network business model is shifting from a network-operator-oriented business to a more open system with several actors. In this context, the Network Slice provider will play the role of an intermediate entity between the vertical service provider and the resource provider. To deploy a network slice, the netwo...
Article
5G comes with the promise of sub-millisecond latency, which is critical for realizing an array of emerging URLLC services, including industrial, entertainment, telemedicine, automotive, and tactile Internet applications. At the same time, slicing-ready 5G networks face the challenge of accommodating other heterogeneous coexisting services with diff...
Article
We address the fundamental tradeoff between deployment cost and service availability in the context of on-demand content delivery service provision over a telecom operator’s Network Functions Virtualization Infrastructure. In particular, given a specific set of preferences and constraints with respect to deployment cost, availability and computing...
Preprint
The future 5G transport networks are envisioned to support a variety of vertical services through network slicing and efficient orchestration over multiple administrative domains. In this paper, we propose an orchestrator architecture to support vertical services to meet their diverse resource and service requirements. We then present a system mode...
Article
We present the design and implementation of a Content-Delivery-Network-as-a-Service (CDNaaS) architecture, which allows a telecom operator to open up its cloud infrastructure for content providers to deploy virtual CDN instances on demand, at regions where the operator has presence. Using northbound REST APIs, content providers can express performa...
Conference Paper
The switch in video delivery from traditional medium to Over-the-Top based services has been a game changer for stakeholders of the media delivery ecosystem. It has changed the value chain enabling Content Delivery Networks and Content Providers to take the liontextquoterights share at the expense of Internet/Network Service Providers. Even if esta...
Conference Paper
Dynamic Adaptive Streaming over HTTP (DASH) is currently a widely adopted technology for video delivery over the Internet. DASH offers significant advantages, enabling users to switch dynamically between different available video qualities responding to variations in the current network conditions during video playback. This is particularly interes...
Article
Information-Centric Networking (ICN) reconsiders the host-centric Internet paradigm with a view to information or content-based identifiers and where multicast data delivery is the norm. However, Wi-Fi, the predominant means of local wireless connectivity today, but also 3G and 4G technologies, are known to suffer from poor multicast performance. I...
Article
The trend towards the cloudification of the 3GPP LTE mobile network architecture and the emergence of federated cloud infrastructures call for alternative service delivery strategies for improved user experience and efficient resource utilization. We propose Follow-Me Cloud (FMC), a design tailored to this environment, but with a broader applicabil...
Article
The ubiquity of Wi-Fi networks, coupled with their anarchic deployment, gives rise to the problem of accurately determining their topology in order to employ it for tuning and optimization. Knowledge of the Wi-Fi topology is particularly important for reconfiguration mechanisms, such as channel assignment and power control schemes, which depend on...
Article
User-centrism has emerged as a disruptive new communication paradigm. In this article, we lay out its basic principles, study the key factors that have given rise to its adoption, and focus on the new set of challenges it brings about in various aspects of wireless networking. We study user-centric solutions on a case-by-case basis, along the dimen...
Article
Motivated by the increased Wi-Fi coverage in metropolitan areas and the emergence of user-centric wireless access schemes, we focus on the provision of secure, user-centric voice services and explore their potential performance-wise, by designing a VoIP communications scheme tailored to open-access wireless environments, but also with wider applica...
Article
We focus on the problem of efficiently integrating wireless users in future Information-Centric Networks (ICN), where communication is based on publish-subscribe primitives. The current host-centric Internet paradigm is abandoned in favor of information-oriented, rendezvous-based communication, where multicast data delivery is the norm. However, Wi...
Conference Paper
The recently-standardized Precision Time Protocol v2 (PTPv2) aims at achieving sub-microsecond-level synchronization between network clocks. In this work, we make the case for an alternative use of it: Adopting a learning approach, we observe its delay behavior during the protocol message exchange, derive models of its dependence on network load an...
Conference Paper
With the availability of cloud computing infrastructures, migrating business-critical functionality to public clouds is becoming commonplace. Cloud providers typically offer a variety of computing capabilities and pricing options. Therefore, the problem of selecting the ones that suit enterprise needs becomes critical. Our major focus is on the mig...
Conference Paper
We make the case for utilizing the recently standardized IEEE 1588-2008 Precision Time Protocol (PTPv2) to achieve real-time, delay-based, network load estimation. We design and implement a load estimation service which builds upon our measurement-driven scheme for correlating path delay and network load, showing it to minimize estimation error to...
Conference Paper
Full-text available
The recent paradigm shift in the Internet’s usage, from the host-centric to a content-centric communication model, where users request information irrespectively of its location, is coupled with an increasing need for converged and seamless access over heterogeneous wired and wireless networks. By integrating satellite communication components into...
Conference Paper
The recent paradigm shift in the Internet’s usage, from the host-centric communication model to a model where users request information irrespectively of its location, is coupled with an increasing need for converged and seamless access over heterogeneous wired and wireless (fixed, cellular, and satellite) networks. Using a satellite network emulat...
Article
Low-cost wireless LAN equipment operating in unlicensed spectrum has revolutionized local area communications, introducing novel schemes for open wireless connectivity and even new business models. The ease of deployment of Wi-Fi has made it ubiquitous in densely populated urban areas, and it was just a matter of time before wireless communities em...
Conference Paper
Full-text available
The ASPECTS project considered an underlying dynamic spectrum access radio network, spectrum sensing technology and techniques, and spectrum sharing policies and rules and addressed vulnerabilities in all spectrum sharing phases, i.e. spectrum monitoring, negotiation, dissemination of access rules and sharing implementation. In the following sectio...
Conference Paper
The low cost and ease of installation of Wi-Fi equipment operating in unlicensed spectrum have made dense Wi-Fi deployments a reality in most modern urban areas. With the lack of many non-overlapping frequencies to operate on, interference among neighbor Wi-Fi cells can cause significant performance degradation. Here we study the problem of topolog...
Article
Low-cost wireless LAN equipment operating in unlicensed spectrum has revolutionized local area communications, introducing novel schemes for open wireless connectivity and even new business models. The ease of deployment of Wi-Fi has made it ubiquitous in densely populated urban areas, and it was just a matter of time before wireless communities em...
Conference Paper
Full-text available
With the low installation and maintenance cost of IEEE 802.11-based equipment, dense Wi-Fi deployments are a reality, especially in today's urban areas. This vast number of WLANs can be exploited to achieve low-cost ubiquitous wireless Internet access, which is also demostrated by the emergence of community-based wireless access schemes. In our pri...
Article
Full-text available
Recent advances in the fields of Cognitive Radio and the proliferation of open spectrum access promise that spectrum-agile wireless communication will be widespread in the near future, and will bring significant flexibility and potential utility improvements for end users. With spectrum efficiency being a key objective, most relevant research focus...
Article
In densely populated cities, Wi-Fi networks-private or otherwise-are ubiquitous. We focus on the provision of citywide broadband communication capability to mobile users through private Wi-Fi networks that are in range but belong to others. We form a club that relies on indirect reciprocity: Members participate in the club and provide free Wi-Fi ac...
Conference Paper
The density of IEEE 802.11 Wireless Local Area Networks, especially in metropolitan areas, has resulted in almost ubiquitous wireless presence in such environments. Apart from the benefits of increased wireless coverage, though, uncontrolled WLAN deployment has brought to attention interference issues among neighbor wireless networks. Combating int...
Article
We study the problem of interference detection in dense Wi-Fi deployments, which are a reality in most modern metropolitan areas. Interference among neighbor Wi-Fi cells stems from the anarchic deployment of Wi-Fi access points (APs) and the fact that only few APs can operate at the same location on non-overlapping frequencies. Detection of interfe...
Article
We present the design and implementation of a fully decentralized P2PWNC (Peer-to-Peer Wireless Network Confederation) WLAN roaming architecture, enhancing previously published work. We present a proof-of-concept secure VoIP application that is built on top of the existing P2PWNC infrastructure and can provide a low-cost substitute to GSM service....
Conference Paper
In recent years, we have witnessed a trend towards open wireless access, mainly driven by the low cost of IEEE 802.11-capable equipment and its operation in unlicensed spectrum. This trend has many faces; municipalities set up free Wi-Fi hotspots for Internet connectivity in public spaces, while Wi-Fi access is provided as an extra service to custo...
Conference Paper
Driven by their low cost and ease of deployment, as well as their operation in unlicensed spectrum bands, IEEE 802.11-based Wireless Local Area Networks (WLANs), also termed Wi-Fi, have been established as the de facto access technology for local area wireless connectivity. Especially in densely-populated urban areas, WLAN presence is ubiquitous. R...
Conference Paper
Full-text available
The use of licensed spectrum for wireless communication is driven by the need to control interference between different operators. However, with this mode of regulation, spectrum utilization is far from efficient and the growth of wireless networks is hindered by the shortage of free frequency bands and the vast investments for the acquisition of a...
Conference Paper
Full-text available
IEEE 802.11k is an extension of the IEEE 802.11 specification for radio resource measurements. In an IEEE 802.11k-enabled wireless LAN, an access point or other network element may request from a client or another access point to monitor and report the load of a channel. We call the latter a channel monitoring station. In this paper we propose a mec...
Conference Paper
Full-text available
Wide deployment of Wireless Local Area Networks (WLANs), especially in modern densely-populated metropolitan areas, constitutes a leap towards ubiquitous wireless network access. This is largely attributable to their low installation and operational cost and mainly their operation in unlicensed bands. Together with the clear benefits of increased W...
Article
Full-text available
In the last few years, we have witnessed a tremendous growth in the number of wireless devices operating in unlicensed spectrum. Wi-Fi equipment has become standard in laptops and handhelds, while Blue-tooth prevails for short-range connectivity. The vision of the Internet of Things, where myriads of heterogeneous devices will interconnect over wir...
Conference Paper
We have designed and implemented P2PWNC, a fully distributed, open to all, autonomous WLAN roaming scheme that can be used in a community to provide various multimedia communication services. Here we discuss various security related issues and the support provided by P2PWNC for several aspects of communication and roaming privacy. We also report on...
Conference Paper
The purpose of this work is to experimentally evaluate the quality of voice and data services over community-based WLAN access networks. We use P2PWNC, the Wireless LAN roaming architecture that we have developed, as the basis for the provision of ubiquitous citywide WLAN ac- cess and set up an infrastructure for secure voice and data communication...
Article
Wireless Community Networks (WCNs) are metropolitan-area networks with nodes owned and managed by volunteers. These networks can be used to build large scale public infrastructures for providing ubiquitous wireless broadband access through the private contributions of individual community members who use their hotspots to forward foreign traffic fr...
Conference Paper
Wireless Community Networks (WCNs) are wide-area wireless networks whose nodes are owned and managed by volunteers. We focus on the provision of Internet access to mobile users through WCN-controlled wireless LAN access points (APs). We rely on reciprocity: a person participates in the WCN and provides 'free' Internet access to mobile users in orde...
Article
In metropolitan areas, public infrastructures for high-speed wireless networking can be built through the private contributions of individual "micro-operators" who use their Internet-connected Wireless LANs (WLANs) to forward foreign traffic from and to nearby low-mobility clients. We have designed a practical WLAN aggregation scheme that (1) assum...
Conference Paper
In metropolitan areas, public infrastructures for high-speed wireless networking can be built through the private contributions of individual "microproviders" who use their Internet-connected wireless LANs (WLANs) to forward foreign traffic from/to nearby low-mobility clients. We have designed a practical WLAN aggregation scheme that: (1) Assumes t...
Article
Abstract—In metropolitan areas, public infrastructures for high-speed wireless networking can be built through the private contributions of individual “microoperators” who use their Internet-connected Wireless LANs (WLANs) to forward foreign traffic from and to nearby low-mobility clients. We have designed a practical WLAN aggregation scheme that (...
Article
We present the design and implementation of a protocol for supporting Wireless LAN (WLAN) roaming federations. Unlike existing approaches, which incur significant management overhead, our protocol is designed specifically with reducing management complexity in mind. More specifically, the next generation operators that oversee our WLAN federations...
Article
We have introduced the concept of a Peer-to-Peer Wireless Network Confederation (P2PWNC) in [1,2]. In this paper we present ongoing work towards implementing Traffic Logging in the context of a homogeneous P2PWNC that is WLAN-based. We first provide a brief overview of these concepts. The P2PWNC is a collection of wireless network domains. It is al...
Article
The proliferation and growth of modern computer networks have made network management infrastructures an integral part of the administration process. Nevertheless, most of these do not have the no-tion of security assimilated by design. Thus, existing network equipment cannot be managed securely without additional hardware or software se-curity mod...

Citations

... FDI attacks present a serious challenge for IoT systems. This type of attacks is even more damaging with the advent of next-generation networks, as these networks will enable massive access to data and shared services [4,5]. According to a recently commissioned report by the 5G infrastructure public-private partnership (5G PPP) [6], security challenges in IoT systems are likely to be more prominent in 5G networks due to the large number of devices that are often designed without security being a priority. ...