Demo Data from VLDB 2026 / reviewers in the wild / expert
Vasileios Theodorou
dblp:150/4993
· DBLP profile ↗
17ranked-venue papers
8as first author
6since 2021 · last 2024
0000-0002-0249-170XORCID · verified
Domains — the database's venue-derived domains; a paper can count in several
Databases, data management, data science and information retrieval · 6 · 5 first-authorSoftware engineering, systems software and programming languages · 4 · 1 first-author · 1 since 2021Artificial intelligence and machine learning · 2 · 2 first-authorComputer networks · 2 · 2 since 2021Systems, architecture and hardware · 1 · 1 first-authorSecurity and privacy · 1 · 1 since 2021
Expertise — from the expertise taxonomy: the topics of the expert's papers under the CCF categories. A weight counts papers with recency: 1 for a paper about the topic, 0.3 when the topic is its context, halved every five years.
| Network and information security
1 paper |
Authentication and access control · 67% Network security · 33% | |
| Computer networks
1 paper |
Cellular and mobile networks · 100% |
Topics — the 3 heaviest of 4, each with the papers that count most for it
| Topic | Weight | Papers | Last | Evidence papers |
|---|---|---|---|---|
Authentication and access control › trust management
trust and reputation |
0.8 | 1 | 2024 | SLA-Driven Trust and Reputation Management Framework for 5G Distributed Service Marketplaces · IEEE Trans. Dependable Secur. Comput. 2024 |
Authentication and access control
trust management |
0.8 | 1 | 2024 | SLA-Driven Trust and Reputation Management Framework for 5G Distributed Service Marketplaces · IEEE Trans. Dependable Secur. Comput. 2024 |
Cellular and mobile networks
5g |
0.2 | 1 | 2024 | SLA-Driven Trust and Reputation Management Framework for 5G Distributed Service Marketplaces · IEEE Trans. Dependable Secur. Comput. 2024 |
Methods — techniques the papers use, named apart from their topics
reputation scoring · 1.5breach prediction · 1.5
| Year | Publication | Venue | Position |
|---|---|---|---|
| 2024 | Democratizing Predictive Analytics with Generative Artificial Intelligence towards AI-Native NetworksabstractIn the rapidly advancing era of Artificial Intelligence (AI), the transformative force of foundation models has streamlined the automated generation of multi-modal content, corresponding to user intents. At the same time, Machine Learning (ML), particularly Deep Learning (DL), has achieved state-of-the-art performance in optimization and inference tasks of various domains, including telecommunications. However, the segregation of technological domains poses challenges to the integration of powerful AI/ML capabilities towards realizing the vision of "AI-native" networks, such as future 6G networks that will provide ubiquitous intelligence across their infrastructure and service planes and will seamlessly adapt and evolve to support new classes of applications. This paper introduces Auto-TimeGPT, a handsfree Automated ML (AutoML) solution, extending the profound impact of Generative AI (GenAI) for Time Series Analysis, to networks and communications. The contribution includes an out-of-the-box zero-shot approach for anomaly detection and Time Series Forecasting (TSF) which is particularly useful for the Edge-Cloud orchestration framework CODECO, comprehensive in and out-of-domain evaluation, and a limitations analysis. Evaluation results across diverse real-world datasets demonstrate competitive performance with cutting-edge approaches based on Large Language Models (LLMs) and DL models, generalization and optimization ability and effective anomaly detection. The proposed framework democratizes AI analytics in communication and networking domains. Georgios Samaras, Marinela Mertiri, Maria-Evgenia Xezonaki, Vasileios Theodorou, Panteleimon-Konstantinos Chartsias, Theodoros Bozios |
ISCC | 4 |
| 2024 | SLA-Driven Trust and Reputation Management Framework for 5G Distributed Service MarketplacesabstractThe fifth generation (5G) of mobile telecommunications is characterized by massive growth in the number of stakeholders, interconnected devices, and available services distributed under different administrative domains. Distributed marketplaces aim at facilitating stakeholders in the quest and hiring of third party resources and services. Establishing trustworthiness in such an open ecosystem is a cornerstone for the final deployment of these marketplaces in 5G networks and beyond. Hence, building trust management systems that ensure the selection of reliable parties or assets in 5G distributed marketplaces is essential. Thus, a reputation-based trust management framework is proposed to analyze stakeholder behavior patterns and predict trust scores to establish trustworthy relationships across domains. Furthermore, an Service Level Agreement (SLA)-driven reward and punishment mechanism is designed and developed on top of the reputation-based trust framework. Such a mechanism enables continuously adapting trust scores by gathering breach predictions, breach detections, and SLA violations in real time. Furthermore, an edge-based use case is presented to contextualize our reputation-based framework in a tangible enforcement scenario. In conclusion, three experiments were conducted on real-life testbeds demonstrating that our framework fairly distinguishes bad-mouthing attacks with 67% accuracy, when 50% recommenders are corrupted, and is resilient to continuous misbehavior bursts. José María Jorquera Valero, Vasileios Theodorou, Manuel Gil Pérez, Gregorio Martínez Pérez |
IEEE Trans. Dependable Secur. Comput. | 2 |
| 2023 | AI Anomaly Detection for Cloudified Mobile Core ArchitecturesabstractIT systems monitoring is a crucial process for managing and orchestrating network resources, allowing network providers to rapidly detect and react to most impediment causing network degradation. However, the high growth in size and complexity of current operational networks (2022) demands new solutions to process huge amounts of data (including alarms) reliably and swiftly. Further, as the network becomes progressively more virtualized, the hosting of NFV on cloud environments adds a magnitude of possible bottlenecks outside the control of the service owners. In this paper, we propose two deep learning anomaly detection solutions that leverage service exposure and apply it to automate the detection of service degradation and root cause discovery in a cloudified mobile network that is orchestrated by ETSI OSM. A testbed is built to validate these AI models. The testbed collects monitoring data from the OSM monitoring module, which is then exposed to the external AI anomaly detection modules, tuned to identify the anomalies and the network services causing them. The deep learning solutions are tested using various artificially induced bottlenecks. The AI solutions are shown to correctly detect anomalies and identify the network components involved in the bottlenecks, with certain limitations in a particular type of bottlenecks. A discussion of the right monitoring tools to identify concrete bottlenecks is provided. Foivos Michelinakis, Joan S. Pujol Roig, Sara Malacarne, Min Xie 0006, Thomas Dreibholz, Sayantini Majumdar, Wint Yi Poe, Georgios Patounas, Carmen Guerrero, Ahmed Elmokashfi, Vasileios Theodorou |
IEEE Trans. Netw. Serv. Manag. | 11 |
| 2022 | Zero-touch security automation mechanisms for edge NFV: the π-Edge approachabstractThe shift towards distributed computing architectures that push data storage and processing to the edge of the network, is resulting into a convergence of cloud-computing services and next generation mobile network technologies. In order to uniformly manage resources and services in the formed cloud/core to edge/devices continuum and to handle the diversity of multi-party underlying infrastructure technologies in a latency-aware, reliable and trustworthy fashion, management automation has become more crucial than ever. In this work, we present the security analytics mechanisms of the π-Edge platform–our edge management platform that embodies zero-touch automation features for interoperability, Quality of Service (QoS) assurance, resilience and trust. To this end, we introduce a declarative NFV MANO Information Model (IM) and methods for automatically enhancing Network Slices at the edge, with security services that i) continuously monitor user-plane traffic on the links between Virtual Network Functions (VNFs), ii) detect possible network vulnerabilities or malicious behaviour and iii) apply relevant actions to effectively observe and mitigate identified threats. The implementation of such mechanisms is evaluated through experimentation on a use case of DDoS attacking scenarios, showcasing the usability and the benefits of our proposed solution. Alexandros Valantasis, Nikos Psaromanolakis, Vasileios Theodorou |
CNSM | 3 |
| 2021 | MEDAL: An AI-Driven Data Fabric Concept for Elastic Cloud-to-Edge Intelligence
Vasileios Theodorou, Ilias Gerostathopoulos, Iyad Alshabani, Alberto Abelló, David Breitgand |
AINA (3) | 1 |
| 2021 | Dynamic Slice Scaling Mechanisms for 5G Multi-domain EnvironmentsabstractNetwork slicing is an essential 5G innovation whereby the network is partitioned into logical segments, so that Communication Service Providers (CSPs) can offer differentiated services for verticals and use cases. In many 5G use cases, network requirements vary over time and CSPs must dynamically adapt network slices to satisfy the contractual network slice QoS, cooperating and using each others’ resources, e.g. when resources of a single CSP are not sufficient or suitable to maintain all it’s current SLAs. While this need for dynamic cross-CSP cooperation is widely recognized, realization of this need is not yet possible due to gaps both in business processes and in technical capabilities.In this paper, we present a 5GZORRO approach to dynamic cross-CSP slice scaling. Our approach both enables CSPs to collaborate, providing security and trust with smart multi-party contracts, and facilitates thus achieved collaboration to enable resource sharing across multiple administrative domains, either during slice establishment or when already existing slice needs to expand or shrink. Our approach allows automating both business and technical processes involved in dynamic lifecycle management of cross-CSP network slices, following ETSI’s Zero-Touch Network and Service Management (ZSM) closed-loop architecture, and relying on resource-sharing Marketplace, Distributed Ledger (DL), and Operational Data Lake. We show how this approach is realized in truly Cloud Naive way, with Kubernetes as both business and technical cross-domain orchestrator. We then showcase applicability of the proposed solution for dynamic scaling of Content Delivery Network (CDN) service. David Breitgand, Alexios Lekidis, Rasoul Behravesh, Avi Weit, Pietro G. Giardina, Vasileios Theodorou, Cristina Emilia Costa, Katherine Barabash |
NetSoft | 6 |
| 2020 | A Multi-Criteria Decision Making Method for Network Slice Edge Infrastructure SelectionabstractIn the era of 5G networks, the demand for high quality service provisioning is growing extremely fast. The enabling of Network Function Virtualization and Network Slicing in the scope of 5G network aims to meet the strict requirements of various business cases. Alongside, the complexity of deployment such services becomes also higher, regarding the differences between infrastructure capabilities and the plethora of various individual requirements. This fact makes the selection of the appropriate infrastructure for slice deployment a complex, but also, a major process, as the optimization of the selection leads to the satisfaction of the user and the better resource allocation from the provider's perspective. In this work, an Edge PoP Selection framework for network slice deployment is proposed. This framework takes into account the user's hard and soft requirements and performs a two-stage selection. The selection of the appropriate infrastructure is based on a multi-criteria decision making method. The proposed framework is evaluated and compared with simple filtering and single-objective selection approaches. The promising results show the importance of the two stage framework in order to simultaneously meet the user's requirements and the optimal utilization of the resources. Ioannis Dimolitsas, Dimitrios Dechouniotis, Vasileios Theodorou, Panagiotis Papadimitriou 0001, Symeon Papavassiliou |
NetSoft | 3 |
| 2020 | Towards Cross-Slice Communication for Enhanced Service Delivery at the Network EdgeabstractThe increasing resource demand and diversity of network services is taken under serious consideration by the various stakeholders, driving the architecture design of 5G (and beyond) networks. Network slicing, as a prominent aspect of next-generation network architectures, aims at satisfying the diverse service requirements in terms of throughput, latency, reliability, and/or security. However, the prevailing way of slice provisioning, i.e., in the form of isolated bundles of computing, storage, and network resources, makes cross-slice communication inefficient, especially at the network edge. This inevitably hinders opportunities for Business-to-Business (B2B) synergies at the event of service co-location. In this paper, we study this novel aspect of network slicing, i.e., cross-slice communication (CSC). We particularly promote a form of optimized CSC, at which two co-located slices can establish peering in a secure and controlled manner, by confining peering traffic within the boundaries of the datacenter, while still preserving the important aspect of resource isolation. Such optimized CSC can foster synergies between service providers without additional latency or traffic in the backhaul/transport network. In this context, we investigate various ways to establish optimized CSC at edge computing infrastructures, based on functionalities offered by state-of-the-art management and orchestration (MANO) frameworks, such as OpenSourceMANO. Ioakeim Fotoglou, George Papathanail, Angelos Pentelas, Panagiotis Papadimitriou 0001, Vasileios Theodorou, Dimitrios Dechouniotis, Symeon Papavassiliou |
NetSoft | 5 |
| 2020 | Network Slicing for Multi-tenant Edge Processing over Shared IoT InfrastructureabstractEmerging 5G technologies are expected to further unleash the IoT potential, providing the necessary scalability and flexibility for supporting diverse classes of service. In particular, 5G Network Slicing combined with network infrastructure virtualization and programmability can equip cellular IoT with instruments to efficiently facilitate critical, low latency IoT scenaria, as well as massive IoT scenaria of wide-area IoT applications. In parallel, the continuous enhancement of Edge networking infrastrucutre with more capacity and intelligence, presents great opportunities to further improve IoT applications' network-related quality of experience and resource efficiency. In this paper, we focus on massive IoT usage scenaria and we introduce a Network Slicing approach for IoT infrastructure shareability and multi-tenant edge processing of isolated IoT applications. To this end, we propose the 2-tier distribution of IoT Gateways at the network edge and their virtualization as extendable edge platforms and we present a novel architecture building on the NFV MANO architectural framework for slice orchestration and lifecycle management. Initial results from the system prototyping of our solution showcase the automated end-to-end instantiation and readiness of IoT Slices in the order of few minutes. Vasileios Theodorou, Maria-Evgenia Xezonaki |
NetSoft | 1 |
| 2017 | Frequent patterns in ETL workflows: An empirical approach
Vasileios Theodorou, Alberto Abelló, Maik Thiele, Wolfgang Lehner |
Data Knowl. Eng. | 1 |
| 2017 | Data generator for evaluating ETL process quality
Vasileios Theodorou, Petar Jovanovic 0001, Alberto Abelló, Emona Nakuçi |
Inf. Syst. | 1 |
| 2016 | Quality measures for ETL processes: from goals to implementationabstractSummary Extraction transformation loading (ETL) processes play an increasingly important role for the support of modern business operations. These business processes are centred around artifacts with high variability and diverse lifecycles, which correspond to key business entities. The apparent complexity of these activities has been examined through the prism of business process management, mainly focusing on functional requirements and performance optimization. However, the quality dimension has not yet been thoroughly investigated, and there is a need for a more human‐centric approach to bring them closer to business‐users requirements. In this paper, we take a first step towards this direction by defining a sound model for ETL process quality characteristics and quantitative measures for each characteristic, based on existing literature. Our model shows dependencies among quality characteristics and can provide the basis for subsequent analysis using goal modeling techniques. We showcase the use of goal modeling for ETL process design through a use case, where we employ the use of a goal model that includes quantitative components (i.e., indicators) for evaluation and analysis of alternative design decisions. Copyright © 2015 John Wiley & Sons, Ltd. Vasileios Theodorou, Alberto Abelló, Wolfgang Lehner, Maik Thiele |
Concurr. Comput. Pract. Exp. | 1 |
| 2015 | POIESIS: a Tool for Quality-aware ETL Process RedesignabstractWe present a tool, called POIESIS, for automatic ETL process enhancement. ETL processes are essential data-centric activities in modern business intelligence environments and they need to be examined through a viewpoint that concerns their quality characteristics (e.g., data quality, performance, manageability) in the era of Big Data.\nPOIESIS responds to this need by providing a user-centered environment for quality-aware analysis and redesign of ETL flows. It generates thousands of alternative flows by adding flow patterns to the initial flow, in varying positions and combinations, thus creating alternative design options in a multidimensional space of different quality attributes.\nThrough the demonstration of POIESIS we introduce the tool's capabilities and highlight its efficiency, usability and modifiability, thanks to its polymorphic design. © 2015, Copyright is with the authors. Vasileios Theodorou, Alberto Abelló, Maik Thiele, Wolfgang Lehner |
EDBT | 1 |
| 2014 | Quality Measures for ETL Processes
Vasileios Theodorou, Alberto Abelló, Wolfgang Lehner |
DaWaK | 1 |
| 2014 | Bijoux: Data Generator for Evaluating ETL Process QualityabstractObtaining the right set of data for evaluating the fulfillment of different quality standards in the extract-transform-load (ETL) process design is rather challenging. First, the real data might be out of reach due to different privacy constraints, while providing a synthetic set of data is known as a labor-intensive task that needs to take various combinations of process parameters into account. Additionally, having a single dataset usually does not represent the evolution of data throughout the complete process lifespan, hence missing the plethora of possible test cases. To facilitate such demanding task, in this paper we propose an automatic data generator (i.e., Bijoux). Starting from a given ETL process model, Bijoux extracts the semantics of data transformations, analyzes the constraints they imply over data, and automatically generates testing datasets. At the same time, it considers different dataset and transformation characteristics (e.g., size, distribution, selectivity, etc.) in order to cover a variety of test scenarios. We report our experimental findings showing the effectiveness and scalability of our approach. Emona Nakuçi, Vasileios Theodorou, Petar Jovanovic 0001, Alberto Abelló |
DOLAP | 2 |
| 2014 | A Framework for User-Centered Declarative ETLabstractAs business requirements evolve with increasing information density and velocity, there is a growing need for efficiency and automation of Extract-Transform-Load (ETL) processes. Current approaches for the modeling and optimization of ETL processes provide platform-independent optimization solutions for the (semi-)automated transition among different abstraction levels, focusing on cost and performance. However, the suggested representations are not abstract enough to communicate business requirements and the role of the process quality in a user-centered perspective has not yet been adequately examined. In this paper, we introduce a novel methodology for the end-to-end design of ETL processes that takes under consideration both functional and non-functional requirements. Based on existing work, we raise the level of abstraction for the conceptual representation of ETL operations and we show how process quality characteristics can generate specific patterns on the process design. Vasileios Theodorou, Alberto Abelló, Maik Thiele, Wolfgang Lehner |
DOLAP | 1 |
| 2014 | Towards Mitigation of Low and Slow Application DDoS AttacksabstractDistributed Denial of Service attacks are a growing threat to organizations and, as defense mechanisms are becoming more advanced, hackers are aiming at the application layer. For example, application layer Low and Slow Distributed Denial of Service attacks are becoming a serious issue because, due to low resource consumption, they are hard to detect. In this position paper, we propose a reference architecture that mitigates the Low and Slow Distributed Denial of Service attacks by utilizing Software Defined Infrastructure capabilities. We also propose two concrete architectures based on the reference architecture: a Performance Model-Based and Off-The-Shelf Components based architecture, respectively. We introduce the Shark Tank concept, a cluster under detailed monitoring that has full application capabilities and where suspicious requests are redirected for further filtering. Mark Shtern, Roni Sandel, Marin Litoiu, Chris Bachalo, Vasileios Theodorou |
IC2E | 5 |