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Nischal Aryal, Fariba Ghaffari, E. Bertin, Noël Crespi
International audience
Massimo Franceschet, Andrea Antonutti, Luca Donno
We propose a novel model for teaching and learning called Decentralized Autonomous Education (DAE for short). DAE exploits the dual principles of freedom and responsibility, meritocracy and inclusivity, privacy and transparency in the educational process. It also fits well the philosophy of blockchain technology, and more generally of Web3 – the third iteration of the World Wide Web – specifically the tenets of decentralization, disintermediation, incentive and sovereignty of the individual. In this paper, we fully illustrate the DAE model, highlighting the theoretical and practical links between DAE and Web3, dissecting the pros and cons of the proposed learning method and reviewing related pedagogical approaches. Finally, we describe the front-end and back-end design of the DAE app, a decentralized application that implements the DAE learning model.
Xiaoou Liu, Xiaoyi Chen, Qi Bi, Wei Liang · 6 authors
No abstract is available for this record.
Bing Li, Maode Ma
Abstract Named data networking (NDN) has been viewed as a promising future Internet architecture due to its data-centric design. It requires a new security model that is orienting data but not devices. In this paper, an advanced hierarchical identity-based security mechanism by blockchain (AHISM-B) is to be proposed for the NDN networks. On one hand, the hierarchical identity-based cryptology is used to bind the data name to a public key. The valid public parameters would be requested by consumers with the Interest packets so that consumers would compose producers’ public keys to authenticate producers and verify the integrity of the Data packets. On the other hand, a blockchain is employed to manage public parameters to avoid catastrophes due to a single node failure. Both of the security proof result and the formal validation result indicate that the proposed AHISM-B is secure. Moreover, the simulation results show that the performance of our AHISM-B outperforms that of the classic NDN scheme. Especially, the average response delay of the AHISM-B scheme is less by 8% than that of the classic NDN scheme. With the increase of the average arrival rate of Interest packets, the advantage of the AHISM-B could be enhanced further to 11%.
Racin Nygaard
We have built a bare-metal testbed in order to perform large-scale, reproducible evaluations of erasure coding algorithms. Our testbed supports at least 1000 Ethereum Swarm peers running on 30 machines. Running experimental evaluation is time-consuming and challenging. Researchers must consider the experimental software's limitations and artifacts. If not controlled, the network behavior may cause inaccurate measurements. This paper shares the lessons learned from a bare-metal evaluation of erasure coding algorithms and how to create a controlled-environment in a cluster consisting of 1000 Ethereum Swarm peers.
Rikuo Haga, Kodai Toyoda, Yuto Shinoda, Daiki Miyahara · 7 authors
No abstract is available for this record.
Morteza Alizadeh, Karl Andersson, Olov Schelén
Decentralization is essential when trust and performance must not depend on a single organization. Distributed Ledger Technologies (DLTs) and Decentralized Hash Tables (DHTs) are examples where the DLT is useful for transactional events, and the DHT is useful for large-scale data storage. The combination of these two technologies can meet many challenges. The blockchain is a DLT with immutable history protected by cryptographic signatures in data blocks. Identification is an essential issue traditionally provided by centralized trust anchors. Self-sovereign identities (SSIs) are proposed decentralized models where users can control and manage their identities with the help of DHT. However, slowness is a challenge among decentralized identification systems because of many connections and requests among participants. In this article, we focus on decentralized identification by DLT and DHT, where users can control their information and store biometrics. We survey some existing alternatives and address the performance challenge by comparing different decentralized identification technologies based on execution time and throughput. We show that the DHT and machine learning model (BioIPFS) performs better than other solutions such as uPort, ShoCard, and BBID.
Kumar, Navdeep, Alexandre Reiffers-Masson, Isabel Amigo, Santiago Ruano Rincón · 6 authors
We present a new stochastic model for the evolution of Directed Acyclic Graphs (DAG)-based distributed ledgers (DL), under the presence of heterogeneous delay. This model is used to analyse the performance metrics of the DL, showing in particular that the number of unapproved messages does not diverge to infinity, even under the presence of delay. We propose an analysis based on conveniently defined sets, as well as an alternative drift-based analysis. The former allows to get a bound on the number of unapproved messages, while the latter, through a simpler analysis, allows to probe the existence of such bound. For particular scenarios, we are able to derive the expected value of the drift of unapproved messages, through a Markov process-based approach. State-of-the-art mathematical models trying to capture the impact of delays on the performance of such DLs rely on some particular simplifications. In contrast, through our model, we are able to analytically derive similar performance guarantees, in a more realistic setup. In particular, we focus on IOTA foundation's tangle, while our results can be extended to other DAG-based distributed ledgers. We compare our results to results obtained in a real testbed, showing good accordance between them.
Ashish Adhikari, Danda B. Rawat
Evolution of the cellular network has created many new capabilities that were previously unavailable in the legacy standards. High throughput and low latency communications are the hallmark of the new 5G-NR standard. Caching at the D2D layer in 5G presents tremendous opportunity for further enhancement of the 5G standard and could be the driving factor behind new set of verticals to be offered and made available over 5G and Beyond 5G (B5G) networks.Smart contracts, applications deployed on a distributed blockchain, similarly provide a huge range of novel opportunities in programming and managing a distributed network system while maintaining security. Since D2D communications are fundamentally limited by their localized communication, a smart contract based approach is presented here to open up the D2D layers in B5G networks to any content provider or network operator participating in the shared blockchain network. In this work, three different priority models are evaluated for performance with respect to caching decisions driven by a genetic algorithm based search for decision optimality. Findings suggest that integration of a priority scheme with a smart contract enforced caching at D2D layer significantly influences the Radio Access Network (RAN) performance in terms of the cost and delay for proposed D2D wireless network.
Yeow Meng Chee, Tuvi Etzion, Han Mao Kiah, Alexander Vardy
<p style='text-indent:20px;'>The Hamming ball of radius <inline-formula><tex-math id="M1">\begin{document}$ w $\end{document}</tex-math></inline-formula> in <inline-formula><tex-math id="M2">\begin{document}$ \{0,1\}^n $\end{document}</tex-math></inline-formula> is the set <inline-formula><tex-math id="M3">\begin{document}$ \mathcal{B}(n,w) $\end{document}</tex-math></inline-formula> of all binary words of length <inline-formula><tex-math id="M4">\begin{document}$ n $\end{document}</tex-math></inline-formula> and Hamming weight at most <inline-formula><tex-math id="M5">\begin{document}$ w $\end{document}</tex-math></inline-formula>. We consider injective mappings <inline-formula><tex-math id="M6">\begin{document}$ \varphi : \{0,1\}^m \to \mathcal{B}(n,w) $\end{document}</tex-math></inline-formula> with the following <i>domination property:</i> every position <inline-formula><tex-math id="M7">\begin{document}$ j \in [n] $\end{document}</tex-math></inline-formula> is dominated by some position <inline-formula><tex-math id="M8">\begin{document}$ i \in [m] $\end{document}</tex-math></inline-formula>, in the sense that if position <inline-formula><tex-math id="M9">\begin{document}$ i $\end{document}</tex-math></inline-formula> in <inline-formula><tex-math id="M10">\begin{document}$ {\mathit{\boldsymbol{x}}} \in \{0,1\}^m $\end{document}</tex-math></inline-formula> is "switched off" (equal <i>zero</i>), then necessarily position <inline-formula><tex-math id="M11">\begin{document}$ j $\end{document}</tex-math></inline-formula> in its image <inline-formula><tex-math id="M12">\begin{document}$ \varphi({\mathit{\boldsymbol{x}}}) $\end{document}</tex-math></inline-formula> is switched off. This property may be described more precisely in terms of a bipartite <i>domination graph</i> <inline-formula><tex-math id="M13">\begin{document}$ G = \bigl([m] \cup [n], E\bigr) $\end{document}</tex-math></inline-formula> with no isolated vertices; for all <inline-formula><tex-math id="M14">\begin{document}$ (i,j) \in E $\end{document}</tex-math></inline-formula> and all <inline-formula><tex-math id="M15">\begin{document}$ {\mathit{\boldsymbol{x}}}\in \{0,1\}^m $\end{document}</tex-math></inline-formula>, we require that <inline-formula><tex-math id="M16">\begin{document}$ x_i = 0 $\end{document}</tex-math></inline-formula> implies <inline-formula><tex-math id="M17">\begin{document}$ y_j = 0 $\end{document}</tex-math></inline-formula>, where <inline-formula><tex-math id="M18">\begin{document}$ {\mathit{\boldsymbol{y}}} = \varphi({\mathit{\boldsymbol{x}}}) $\end{document}</tex-math></inline-formula>. Although such domination mappings recently found applications in the context of coding for high-performance interconnects, to the best of our knowledge, they were not previously studied. The concept of domination mapping is thus interesting from both practical and combinatorial points of view. <p style='text-indent:20px;'>In this paper, we begin with simple necessary conditions for the existence of an <i><inline-formula><tex-math id="M19">\begin{document}$ (m,n,w) $\end{document}</tex-math></inline-formula>-domination mapping <inline-formula><tex-math id="M20">\begin{document}$ \varphi : \{0,1\}^m \to \mathcal{B}(n,w) $\end{document}</tex-math></inline-formula></i>. We then provide several explicit constructions of such mappings, which show that the necessary conditions are also sufficient when <inline-formula><tex-math id="M21">\begin{document}$ w = 1 $\end{document}</tex-math></inline-formula>, when <inline-formula><tex-math id="M22">\begin{document}$ w = 2 $\end{document}</tex-math></inline-formula> and <inline-formula><tex-math id="M23">\begin{document}$ m $\end{document}</tex-math></inline-formula> is odd, or when <inline-formula><tex-math id="M24">\begin{document}$ m \leqslant 3w $\end{document}</tex-math></inline-formula>. One of our main results herein is a proof that the trivial necessary condition <inline-formula><tex-math id="M25">\begin{document}$ | \mathcal{B}(n,w)| \geqslant 2^m $\end{document}</tex-math></inline-formula> is, in fact, sufficient for the existence of an <inline-formula><tex-math id="M26">\begin{document}$ (m,n,w) $\end{document}</tex-math></inline-formula>-domination mapping whenever <inline-formula><tex-math id="M27">\begin{document}$ m $\end{document}</tex-math></inline-formula> is sufficiently large. We also present a polynomial-time algorithm that, given any <inline-formula><tex-math id="M28">\begin{document}$ m $\end{document}</tex-math></inline-formula>, <inline-formula><tex-math id="M29">\begin{document}$ n $\end{document}</tex-math></inline-formula>, and <inline-formula><tex-math id="M30">\begin{document}$ w $\end{document}</tex-math></inline-formula>, determines whether an <inline-formula><tex-math id="M31">\begin{document}$ (m,n,w) $\end{document}</tex-math></inline-formula>-domination mapping exists for a domination graph with an equitable degree distribution.
Runze Cheng, Yao Sun, Yi‐Jing Liu, Le Xia · 6 authors
Cache-enabled device-to-device (D2D) communication is a potential approach to tackle the resource shortage problem. However, public concerns of data privacy and system security still remain, which thus arises an urgent need for a reliable caching scheme. Fortunately, federated learning (FL) with a distributed paradigm provides an effective way to privacy issue by training a high-quality global model without any raw data exchanges. Besides the privacy issue, blockchain can be further introduced into the FL framework to resist the malicious attacks occurred in D2D caching networks. In this study, we propose a double-layer blockchain-based deep reinforcement FL (BDRFL) scheme to ensure privacy-preserved and caching-efficient D2D networks. In BDRFL, a double-layer blockchain is utilized to further enhance data security. Simulation results first verify the convergence of the BDRFL-based algorithm, and then demonstrate that the download latency of the BDRFL-based caching scheme can be significantly reduced under different types of attacks when compared to some existing caching policies.
Lorenza Giupponi, Francesc Wilhelmi
The innovation provided by network virtualization in 5G, together with standardization and openness boosted by the Open Radio Access Network (O-RAN) Alliance, has paved the way to a collaborative future in cellular systems, driven by flexible network sharing. Such advents are expected to attract new players like content providers and verticals, increasing competitiveness in the telecom market. However, scalability and trust issues are expected to arise, given the criticality of ownership traceability and resource exchanging in a sharing ecosystem. To address that, we propose integrating blockchain technology for enabling mobile operators and other players to exchange radio access network (RAN) resources (e.g., infrastructure) in the form of virtual network functions autonomously and dynamically. Blockchain will provide automation, robustness, trustworthiness, and reliability to mobile networks, thus bringing confidence to open RAN environments. In particular, we define a novel O-RAN-based blockchain-enabled architecture that allows automating RAN sharing procedures through either auction or marketplace-based mechanisms. The potential advantages of the proposed solution are demonstrated through simulation results. The used simulation platform is openly released.
Hazay, Carmit, Venkitasubramaniam, Muthuramakrishnan, Weiss, Mor
Leakage-resilient cryptography aims to protect cryptographic primitives from so-called "side channel attacks" that exploit their physical implementation to learn their input or secret state. Starting from the works of Ishai, Sahai and Wagner (CRYPTO`03) and Micali and Reyzin (TCC`04), most works on leakage-resilient cryptography either focus on protecting general computations, such as circuits or multiparty computation protocols, or on specific non-interactive primitives such as storage, encryption and signatures. This work focuses on leakage-resilience for the middle ground, namely for distributed and interactive cryptographic primitives. Our main technical contribution is designing the first secret-sharing scheme that is equivocal, resists adaptive probing of a constant fraction of bits from each share, while incurring only a constant blowup in share size. Equivocation is a strong leakage-resilience guarantee, recently introduced by Hazay et al. (ITC`21). Our construction is obtained via a general compiler which we introduce, that transforms any secret-sharing scheme into an equivocal scheme against adaptive leakage. An attractive feature of our compiler is that it respects additive reconstruction, namely, if the original scheme has additive reconstruction, then the transformed scheme has linear reconstruction. We extend our compiler to a general paradigm for protecting distributed primitives against leakage, and show its applicability to various primitives, including secret sharing, verifiable secret sharing, function secret sharing, distributed encryption and signatures, and distributed zero-knowledge proofs. For each of these primitives, our paradigm transforms any construction of the primitive into a scheme that resists adaptive party corruptions, as well as adaptive probing leakage of a constant fraction of bits in each share when the share is stored in memory (but not when it is used in computations). Moreover, the transformation incurs only a constant blowup in the share size, and respects additive reconstruction - an important feature for several of these primitives, such as function secret sharing and distributed encryption.
Norah Saleh Alghamdi, Mohammad Ayoub Khan
Wireless sensor networks (WSNs) and Internet of Things (IoT) have gained more popularity in recent years as an underlying infrastructure for connected devices and sensors in smart cities. The data generated from these sensors are used by smart cities to strengthen their infrastructure, utilities, and public services. WSNs are suitable for long periods of data acquisition in smart cities. To make the networks of smart cities more reliable for sensitive information, the blockchain mechanism has been proposed. The key issues and challenges of WSNs in smart cities is efficiently scheduling the resources; leading to extending the network lifetime of sensors. In this paper, a linear network coding (LNC) for WSNs with blockchain-enabled IoT devices has been proposed. The consumption of energy is reduced for each node by applying LNC. The efficiency and the reliability of the proposed model are evaluated and compared to those of the existing models. Results from the simulation demonstrate that the proposed model increases the efficiency in terms of the number of live nodes, packet delivery ratio, throughput, and the optimized residual energy compared to other current techniques.
Ashley Mayle
Existing communication protocols in security networks are highly centralized. While this naively makes the controls easier to physically secure, external actors require fewer resources to disrupt the system because there are fewer points in the system can be interrupted without the entire system failing. We present a solution to this problem using a proof-of-work-based blockchain implementation built on MultiChain. We construct a test-bed network containing visual imagers and microwave sensor information. These data types are ubiquitous in perimeter security systems and allow a realistic representation of a real-world network architecture. The cameras in this system use an object detection algorithm to find important targets in the scene. The raw data from both the sensors and imagers are placed in a transaction. These transactions are then bundled into blocks and broadcast to the rest of the network using the Bitcoin-based MultiChain protocol. We develop five tests to examine the security metrics of our network. We performed the five security metric test using different sized networks from 7 to 39 nodes to determine how the metrics scale with respect to size. We find that when compared to a centralized architecture our implementation provides a resiliency increase that is expected from a blockchain- based protocol without slowing the system so much that a human operator would notice. Furthermore, our approach is able to detect tampering in real time. Based on these results, we theorize that security networks in general could use a blockchain- based approach in a meaningful way.
Khizra Asaf, Rana Asif Rehman, Byung-Seo Kim
No abstract is available for this record.
Kai Lei, Junjie Fang, Qichao Zhang, Junjun Lou · 8 authors
No abstract is available for this record.
Bart Spinnewyn, Steven Latré, Juan Felipe Botero
Neutral host SCPs represent a key element of the 5G vision of ultra-dense mobile networks. However, current business models mostly focus on multi-year agreements for large venues, such as stadiums and hotel chains. These business agreements are regulated through binding SLAs, which tend to be too cumbersome and costly for smaller-scale SCPs. As a result, the neutral host model does not scale up to its full potential. In this article, we propose a framework to enable the participation of small- to medium-sized players in the cellular market as providers offering network resources to MNOs. To this purpose, we review the current and emerging spectrum and technology opportunities that SCPs can use for neutral host deployments. We also propose the use of blockchain-enabled smart contracts as a simple and cost-efficient alternative to traditional SLAs for small-scale SCPs. To demonstrate this, we describe a proof of concept implementation of an Ethereum-based smart contract platform for best effort service between an SCP and an MNO. Our simulations on potential smart contract-based deployments in city center Dublin show that the received signal strength in the considered area will increase by an average of 10 percent.
Asuquo A. Okon, Nishant Jagannath, Ibrahim Elgendi, Jaafar M. H. Elmirghani · 6 authors
Despite increase in deployment of BS, MNOs are still faced with the daunting challenge of providing adequate coverage and capacity in indoor environments. Furthermore, the trust-less environment in which MNOs operate makes it further challenging to achieve interoperability across carriers. Recently the concept of mOs has emerged as a promising solution through deployment of small cells. However, their success has been severely hampered by the absence of a framework for creating and managing business agreements between key stakeholders, i.e., MNOs and mOs. This article proposes a blockchain-enabled SDN approach for managing radio spectrum access between MNOs using smart contracts over small cell networks. Specifically, our solution uses a smart contract to validate transactions between MNOs. Simulation results show that our solution guarantees seamless handoff and high availability between different operators in contrast to a break in connectivity in the absence of an agreement.
Hakima Khelifi, Senlin Luo, Boubakr Nour, Hassine Moungla · 6 authors
No abstract is available for this record.
Rudrashish Pal
Today's state of the art blockchains suffer from two major setbacks. The first among these, bootstrapping, is the introduction of new nodes into the peer-to-peer (P2P) network in the presence of adversarial nodes. It is crucial that new nodes are prevented from joining adversarial nodes to protect the integrity of the network. The second challenge that today's blockchains face is that of storage efficiency. Blockchains use replication to store the data (or ledger) among users. Users acting as full nodes need to store the entire ledger. As opposed to replication, coding techniques such as fountain codes can be utilised to create an efficient distributed storage system.
Latif U. Khan, Ibrar Yaqoob, Muhammad Imran, Zhu Han · 5 authors
Internet of everything (IoE)-based smart services are expected to gain immense popularity in the future, which raises the need for next-generation wireless networks. Although fifth-generation (5G) networks can support various IoE services, they might not be able to completely fulfill the requirements of novel applications. Sixth-generation (6G) wireless systems are envisioned to overcome 5G network limitations. In this article, we explore recent advances made toward enabling 6G systems. We devise a taxonomy based on key enabling technologies, use cases, emerging machine learning schemes, communication technologies, networking technologies, and computing technologies. Furthermore, we identify and discuss open research challenges, such as artificial-intelligence-based adaptive transceivers, intelligent wireless energy harvesting, decentralized and secure business models, intelligent cell-less architecture, and distributed security models. We propose practical guidelines including deep Q-learning and federated learning-based transceivers, blockchain-based secure business models, homomorphic encryption, and distributed-ledger-based authentication schemes to cope with these challenges. Finally, we outline and recommend several future directions.
Debarnab Mitra, Lara Dolecek
Traditionally in blockchain systems, the sequence of transactions acts as a decentralized ledger where each node in the network is required to store an identical copy. As a result, the storage space required to store the entire blockchain can become prohibitively large. Erasure coding and network coding techniques were previously introduced to mitigate this storage burden. In this work, we first observe that node failures in the network can occur periodically. Next, we take advantage of this property to develop a coding scheme which corrects a predefined set of possible node erasure patterns. By explicitly focusing on certain erasure patterns, proposed codes have lower storage requirements than erasure codes which correct all possible erasure patterns, and moreover, our codes achieve the minimum average storage per node under the given assumptions.
Vipindev Adat Vasudevan, Ilias Politis, Christos Tselios, Stavros Kotsopoulos
Network coding has emerged as a promising solution to the highly efficient and reliable network requirements for the next generation communication technology. Network coding enabled small cell environment can assure an efficient device to device communication with the high data rate. However, the security challenges inherent to network coding, like pollution attacks, drags a layer of concern over its implementation. Further, the re-encoding of packets at the intermediate nodes makes it difficult to secure network coding enabled communication using standard cryptographic techniques. Homomorphic message authentication codes and signatures are used to tackle this problem. We propose a network coding enabled small cell environment enhanced by blockchain to prevent pollution attacks. The architecture of this blockchain enhanced SECRET small cell along with an analysis of the communication overhead and latency issues are discussed in this paper.