Blockchain Papers

Kevin Werbach

No abstract is available for this record.

Akram Kout, Said Labed, Salim Chıkhı

Mobile Ad hoc network (MANET) is an autonomous system of mobile hosts (nodes) connected by wireless link forming a temporary network without the aid of any established infrastructure or centralized administration. Typical applications of MANETs are: emergency and rescue operations, disaster relief efforts, military operations and exploration mission where cellular infrastructure is unavailable. The main problem of mobile ad hoc networks is to design routing protocols allowing for communication between the hosts. The dynamic nature of ad hoc networks makes this problem especially challenging. Communication in MANET is multi-hop due to limited transmission range; this decentralized operation relies on the cooperative participations of all nodes. MANETs are considered as complex system characterized by high dynamic topology, local interactions, auto-organization and emergence. Modeling and simulation are very important in the design and development of distributed interacting system because of their particular stochastic nature. This article seeks to use agent-based tools for modeling ad hoc network. We focus on Netlogo, an important tool in the modeling and simulation domain of complex system. We have successfully implemented distributed Dijkstra's shortest path algorithm to solve the routing problem. Obtained Results show the quick convergence of Dijkstra's Algorithm to shortest paths relating a source node with all accessible destinations.

Jayavardhana Gubbi, Rajkumar Buyya, Slaven Marusic, Marimuthu Palaniswami

Ubiquitous sensing enabled by Wireless Sensor Network (WSN) technologies cuts\nacross many areas of modern day living. This offers the ability to measure,\ninfer and understand environmental indicators, from delicate ecologies and\nnatural resources to urban environments. The proliferation of these devices in\na communicating-actuating network creates the Internet of Things (IoT),\nwherein, sensors and actuators blend seamlessly with the environment around us,\nand the information is shared across platforms in order to develop a common\noperating picture (COP). Fuelled by the recent adaptation of a variety of\nenabling device technologies such as RFID tags and readers, near field\ncommunication (NFC) devices and embedded sensor and actuator nodes, the IoT has\nstepped out of its infancy and is the the next revolutionary technology in\ntransforming the Internet into a fully integrated Future Internet. As we move\nfrom www (static pages web) to web2 (social networking web) to web3 (ubiquitous\ncomputing web), the need for data-on-demand using sophisticated intuitive\nqueries increases significantly. This paper presents a cloud centric vision for\nworldwide implementation of Internet of Things. The key enabling technologies\nand application domains that are likely to drive IoT research in the near\nfuture are discussed. A cloud implementation using Aneka, which is based on\ninteraction of private and public clouds is presented. We conclude our IoT\nvision by expanding on the need for convergence of WSN, the Internet and\ndistributed computing directed at technological research community.\n

Cándido Caballero‐Gil, Pino Caballero‐Gil, Jezabel Molina‐Gil

ABSTRACT A mobile ad hoc network (MANET) is a type of wireless network without any infrastructure, where nodes must adapt to the changing dynamic situations that result from their mobility. Because of the decentralization of nodes and the security needs of communications, management of MANETs must be self‐organized, which is a major research challenge. In order to cope with the intrinsic properties of MANETs, a new decentralized management system for MANETs called Self‐organizing Life Cycle Management (SLCM) is here fully described and evaluated. Regarding security, node authentication is the most critical component of access control in any network and, in particular, in MANETs. Broadcasting is also a fundamental data dissemination mechanism in these networks. Both aspects have received special attention when defining the proposed SLCM system. In particular, both a strong access control algorithm, based on the cryptographic paradigm of zero‐knowledge proofs, and a three‐step broadcast protocol are here defined. This work includes the performance evaluation of the scheme, and the obtained experimental results show that SLCM significantly improves both the quality and the security of life cycle management of self‐organized MANETs. Copyright © 2012 John Wiley & Sons, Ltd.

Anuj Kumar Chauhan

In this paper, we present a delay based routing algorithm for ad hoc wireless networks. In an ad hoc environment there is no wired infrastructure and the mobile hosts work as a router to maintain the status about the connectivity. A mobile ad hoc network is an autonomous collection of mobile users (nodes) that communicates over relatively bandwidthconstrained wireless links. Each node is equipped with wireless receivers and transmitters using antennas that may be omnidirectional, highly directional, or possibly steer able. Due to nodal mobility, the network topology may change rapidly and unpredictably over time. The network is decentralized, where network organization and message delivery must be executed by the nodes themselves, i.e., routing functionally will be incorporated into mobile nodes. The design of the network protocols for mobile ad hoc network is a complex issue. These networks need efficient distributed algorithm to determine network organization (connectivity), link scheduling, and routing. But, the existing routing algorithms designed for ad hoc wireless networks have slow response, excessive overhead and become unsuitable under the above considerations. The full approach, for referring the internal state of the network relies on Round Trip Time (RTT) measurements only. We consider the RTT mean and RTT variance as fuzzy input variables and delay as a fuzzy output variable. Under such condition the performance of the proposed algorithm is tested. It is shown that under these conditions the algorithm gives better results. The proposed routing algorithm is simulated in MATLAB 6.5.

Isaac Z. Wu, X.‐Y. Li, Min Song, Chuan-Ming Liu

Pervasive computing is an exciting and blooming research field, in which innovative techniques and applications are continuously emerging and aim to provide ambient and personalized services to users with high quality. Ad hoc networks are wireless, self-organizing systems formed by co-operating nodes within communication range of each other that form temporary networks. Their topology is dynamic, decentralized, ever changing and the nodes may move around arbitrarily. The last few years have witnessed a wealth of research ideas on ad hoc networking that are moving rapidly into implemented standards. Technology under development for ad hoc networks and pervasive computing is making important steps toward this end goal possible. However, the security concerns remain a serious impediment to widespread adoption. The underlying radio communication medium for wireless network provides serious exposure to attacks against wireless networks. Wireless ad hoc networks usually cannot depend on traditional infrastructure found in enterprise environments such as dependable power sources, high bandwidth, continuous connectivity, common network services, well-known membership, static configuration, system administration, and physical security. Finally, throw in malicious adversaries with Byzantine collusion threats and you have a very interesting and challenging problem. Without adequate security, enterprises will not be able to profit from the use of wireless ad hoc networks and pervasive computing environment, defense organizations might be unable to guarantee the safety of their personnel in battlefield scenarios, and wireless ad hoc networks and pervasive computing will remain on the drawing board even if the other problems associated with them are solved. This special issue is focused on various aspects of security in ad hoc networks and pervasive computing research and development to report both in-depth research and applications-oriented works. The special issue is intended to foster state-of-the-art research in the area of security in ad hoc networks and pervasive computing. The aim of this special issue is to present a collection of high quality research papers that report the latest research advances in security of ad hoc. In this special issue, we selected seven papers, which can demonstrate advanced works in this field. A detailed overview of the selected works is given below. The first paper, An RC4-Based Lightweight Protocol for Secure Data Transmission on Resource-Constrained Devices, presents a simple, lightweight, but robust security protocol based on the backward property of RC4 stream cipher. The proposed protocol provides data confidentiality, data authentication, data integrity, and data freshness with low overhead and simple operation, allows packets be received in an arbitrary order, achieves semantic security, and does not require frequent key renew. The second paper, PAPA-UIC: A Design Approach and a Framework for Secure Mobile Ad-hoc Networks, proposes a new design approach and a framework for securing a practical type of MANETs. The framework is named PAPA-UIC. The paper proposes a secure routing protocol and solutions to general problems of identity-based cryptography. The routing protocol has several improvements over existing ones. The third paper, RFIDGuard: A Lightweight Privacy and Authentication Protocol for Passive RFID Tags, introduces a protocol which requires little computation and achieves both privacy and authentication simultaneously. The lightweight and secure nature of the RFIDGuard protocol make it particularly suitable for supply chain management. The fourth paper, Using Hidden Markov Model to Detect Rogue Access Points, proposes a statistical based approach to detect rogue access points using a Hidden Markov Model, which is applied to passively measure packet-header data collected at a gateway router. The main idea is to process the sequence of packet traces in order to distinguish the normal packets from the abnormal ones. The approach is scalable and non-intrusive, requiring little deployment cost and effort, and is easy to manage and maintain. The fifth paper, Defending Sybil Attacks Based on Neighboring Relations in Wireless Sensor Networks, develops a mechanism to protect a WSN from Sybil attacks without using any authentication-based method. Furthermore, the detection approach requires no specialized hardware or support devices. The feature that a malicious node creates many fake identities is exploited to distinguish legitimate nodes from Sybil/malicious nodes. Since all of the fake identities forged by the same malicious node are associated with the same physical device, they will have the same legitimate neighbors. Therefore, by collecting the neighboring information of the suspected victim of the Sybil attacks, the legitimate nodes which are the neighbors of the malicious nodes can be determined. In contrast to existing protection schemes, this approach has no requirement for shared keys, secret information, or special hardware support. The sixth paper, An Autonomous Attestation Token to Secure Mobile Agents in Disaster Response, introduces the Autonomous Attestation Token (AAT), a hardware token for mobile computing devices that is capable of guaranteeing the trusted state of a limited set of devices without relying on a networked service. The paper proposes a Local Attestation protocol with user interaction that in conjunction with the AAT prevents unauthorized access to an emergency mobile agent platform. In addition, the paper sketches a possible solution which integrates trusted computing to leverage ad hoc networks and peer-to-peer systems to provide a robust communication platform. The seventh paper, Building Advanced Applications with the Belgian eID, introduces the Belgian Electronic Identity Card. The card enables Belgian citizens to digitally prove their identity and to sign electronic documents. This paper presents two reusable extensions to the Belgian eID technology that opens up new opportunities for application developers. First, a secure and ubiquitously accessible remote storage service is presented. Second, it is shown how the eID card can be used to issue new certificates. The feasibility and reusability of both extensions are validated through the development of several applications in different domains. In conclusion, this issue of Security in Ad hoc offers a groundbreaking view into the recent advances in secure ad hoc networks. This issue offers both academic and industry appeal the former as a basis toward future research directions, and the latter toward viable commercial applications. Finally, we would like to express our gratitude to the Editor-in-Chief, Professor HsiaoHwa Chen for his advice, patience, and encouragements since the beginning until the final stage. Special thanks go to Michelle in Wiley during the production. We thank all anonymous reviewers who spent much of their precious time reviewing all the papers. Their timely reviews and comments greatly helped us select the best papers in this special issue. We also thank all authors who have submitted their papers for consideration for this issue. We hope you will enjoy reading the great selection of papers in this issue.

V. Matossian

Networked systems are continuously growing in scale and complexity. The technical and policy engineering challenges introduced by such a fast growth are currently addressed locally, with limited understanding of their impact on the whole. Such approaches are becoming impractical and insufficient. Next-generation networks need to address these issues by deploying adaptive and self-managing protocols and mechanisms to relax the persistent need for human-driven management. However, achieving these objectives requires conceptual, physical, and logistical modifications to existing systems and protocols. To this end, the traditional top-down approach to network and application design needs to be supplemented by understanding the bottom-up nature of evolving real-world networks.A critical issue that is significantly impacting computer networks and applications is the absence of an in-depth understanding and lack of control over the structural properties, i.e., topology, of large networks. Network topologies define the link relationships between the nodes in the network, and have a direct impact on the performance, resilience, and security of distributed applications. Large scale networks such as the Internet are the result of a time evolving process in which nodes and links between nodes are added, removed, and reconfigured dynamically. This dynamic process takes place in a decentralized manner during which nodes make local adaptations and reconfiguration decisions that optimize local properties. As a result, these local perturbations yield an emergent network that is often unstructured and complex, and have implications at the application-level, particularly impacting routing, search, robustness, and clustering. Understanding the structures emerging out of these adaptations is a complex problem part of the science and study of complexity theory and complex adaptive systems. Tackling this complex problem requires first, identifying canonical metrics to quantify the network topology and second, analyzing the impact of local perturbations of these metrics on the resulting network topology.This thesis identifies three local metrics, transitivity, assortativity, and entropy, and analyzes the impact of their perturbation on the applications of routing, search, robustness, and clustering. The local metric of network entropy is identified as a useful information theoretic measure of homogeneity of a network neighborhood degree. The metric is further used to derive a novel mechanism of clustering detection of the network topology. The overall objective of this thesis is to investigate metrics and mechanisms to better understand the evolution of the network topology and its impact on application-level functionality. The approach is based on concepts of emergence, self-organization and graph theory, and has three key aspects: (1) the identification of canonical local and global graph metrics; (2) the quantitative analysis of the impact of local perturbations on global properties; and (3) the application of the local to global mapping on the problems of routing, search, robustness, and clustering. Adaptations are performed in a decentralized manner in which local nodes use local information to add, remove, or rewire an edge to evolve the topology. Simulations based on annealing optimization are conducted to empirically determine the optimal bounds of the network structures for the selected metrics on selected networks. Further experiments on two modeled networks, random and power-law degree distributed, and two real-world networks, the Gnutella and Canadian Autonomous System networks, show that the impact of optimizing networks with fixed degree distribution on local metrics yield networks with routing, search, robustness, and clustering that are tightly dependent on the network's degree distribution. A key outcome of this thesis is the identification of network entropy minimization as a useful local rewiring strategy to decrease average path length and search cost, while homogenizing the size of network clusters and having a low impact on robustness when applied to power-law degree distributed networks that prevail in real-world networks.

Philipp Obreiter, Birgitta König‐Ries, Michael Klein

In the context of mobile and wireless devices, an information system is no longer a centralized component storing all the relevant data nor is it a decentralized component governed by a common authority. Rather, the information spread across huge numbers of autonomous mobile and wireless devices owned by independent organizations and individuals can be regarded as a highly dynamic, virtual information system. For this vision to become reality, the autonomous devices involved need to be motivated to cooperate. This cooperation needs to occur not only on the application layer, but, depending on the network architecture, also on the lower layers from the link layer on upwards. In this report, we investigate on which protocol layers cooperation is needed and what constitutes uncooperative behavior. We then identify necessary properties of incentive schemes that encourage cooperation and discourage uncooperative behavior. In this context, we examine remuneration types that are a major constituent of incentive schemes. Finally, using the example of ad hoc networks, the most challenging technical basis of a wireless information system, we compare existing incentive schemes to these characteristics.