Reliable Communication in Wireless Networks

Wireless communication systems are increasingly being used in industries and infrastructures since they offer significant advantages such as cost effectiveness and scalability with respect to wired communication system. However, the broadcast feature and the unreliable links in the wireless communication system may cause more communication collisions and redundant transmissions. Consequently, guaranteeing reliable and efficient transmission in wireless communication systems has become a big challenging issue. In particular, analysis and evaluation of reliable transmission protocols in wireless sensor networks (WSNs) and radio frequency identification system (RFID) are strongly required. This thesis proposes to model, analyze and evaluate self-configuration algorithms in wireless communication systems. The objective is to propose innovative solutions for communication protocols in WSNs and RFID systems, aiming at optimizing the performance of the algorithms in terms of throughput, reliability and power consumption. The first activity focuses on communication protocols in WSNs, which have been investigated, evaluated and optimized, in order to ensure fast and reliable data transmission between sensor nodes. The second research topic addresses the interference problem in RFID systems. The target is to evaluate and develop precise models for accurately describing the interference among readers. Based on these models, new solutions for reducing collision in RFID systems have been investigated

RFID Control System for the Embarkation/Disembarkation of Passengers and Vehicles on/from Ferries

Radio-frequency identification (RFID) is a technology which provides automatic identification and real time data acquisition capabilities without requiring additional human resources. This paper presents a control system for the embarkation/ disembarkation of passengers and vehicles on/from ferries, supported by RFID technology. A basic model of a RFID control system is developed to introduce the notion of RFID as a technology capable of access control with certain technical constraints. The ticket check-in process, made automatic by simple entry of a tag into the field of a RFID reader, increases the flow of passengers and vehicles, reduces port congestion, eliminates the possibility of boarding the wrong (by destination) ferry, and significantly reduces the number of cash payments

Reader Scheduling for Tag Access in RFID Systems

International audience"Reader'' and "Tag'' type devices are utilized in the Radio-Frequency IDentification technology for identification and tracking of objects.A tag can be "read'' by a reader when the tag is within the reader's sensing range. However, when tags are present in the intersection area of the sensing ranges of two or more readers, simultaneous activation of the readers may cause "reader collision''. In order to ensure collision-free reading, a scheduling scheme is needed to read tags in the shortest possible time. We study this scheduling problem in a stationary setting and the reader minimization problem in a mobile setting. We show that the optimal schedule construction problem is NP-complete and provide an approximation algorithm that we evaluate our techniques through simulation

Investigation of interference models for RFID systems

The reader-to-reader collision in an RFID system is a challenging problem for communications technology. In order to model the interference between RFID readers, different interference models have been proposed, mainly based on two approaches: single and additive interference. The former only considers the interference from one reader within a certain range, whereas the latter takes into account the sum of all of the simultaneous interferences in order to emulate a more realistic behavior. Although the difference between the two approaches has been theoretically analyzed in previous research, their effects on the estimated performance of the reader-to-reader anti-collision protocols have not yet been investigated. In this paper, the influence of the interference model on the anti-collision protocols is studied by simulating a representative state-of-the-art protocol. The results presented in this paper highlight that the use of additive models, although more computationally intensive, is mandatory to improve the performance of anti-collision protocols

Towards Secure and Scalable Tag Search approaches for Current and Next Generation RFID Systems

The technology behind Radio Frequency Identification (RFID) has been around for a while, but dropping tag prices and standardization efforts are finally facilitating the expansion of RFID systems. The massive adoption of this technology is taking us closer to the well known ubiquitous computing scenarios. However, the widespread deployment of RFID technology also gives rise to significant user security issues. One possible solution to these challenges is the use of secure authentication protocols to protect RFID communications. A natural extension of RFID authentication is RFID tag searching, where a reader needs to search for a particular RFID tag out of a large collection of tags. As the number of tags of the system increases, the ability to search for the tags is invaluable when the reader requires data from a few tags rather than all the tags of the system. Authenticating each tag one at a time until the desired tag is found is a time consuming process. Surprisingly, RFID search has not been widely addressed in the literature despite the availability of search capabilities in typical RFID tags. In this thesis, we examine the challenges of extending security and scalability issues to RFID tag search and suggest several solutions. This thesis aims to design RFID tag search protocols that ensure security and scalability using lightweight cryptographic primitives. We identify the security and performance requirements for RFID systems. We also point out and explain the major attacks that are typically launched against an RFID system. This thesis makes four main contributions. First, we propose a serverless (without a central server) and untraceable search protocol that is secure against major attacks we identified earlier. The unique feature of this protocol is that it provides security protection and searching capacity same as an RFID system with a central server. In addition, this approach is no more vulnerable to a single point-of-failure. Second, we propose a scalable tag search protocol that provides most of the identified security and performance features. The highly scalable feature of this protocol allows it to be deployed in large scale RFID systems. Third, we propose a hexagonal cell based distributed architecture for efficient RFID tag searching in an emergency evacuation system. Finally, we introduce tag monitoring as a new dimension of tag searching and propose a Slotted Aloha based scalable tag monitoring protocol for next generation WISP (Wireless Identification and Sensing Platform) tags

Ensuring Application Specific Security, Privacy and Performance Goals in RFID Systems

Radio Frequency IDentification (RFID) is an automatic identification technology that uses radio frequency to identify objects. Securing RFID systems and providing privacy in RFID applications has been the focus of much academic work lately. To ensure universal acceptance of RFID technology, security and privacy issued must be addressed into the design of any RFID application. Due to the constraints on memory, power, storage capacity, and amount of logic on RFID devices, traditional public key based strong security mechanisms are unsuitable for them. Usually, low cost general authentication protocols are used to secure RFID systems. However, the generic authentication protocols provide relatively low performance for different types of RFID applications. We identified that each RFID application has unique research challenges and different performance bottlenecks based on the characteristics of the system. One strategy is to devise security protocols such that application specific goals are met and system specific performance requirements are maximized. This dissertation aims to address the problem of devising application specific security protocols for current and next generation RFID systems so that in each application area maximum performance can be achieved and system specific goals are met. In this dissertation, we propose four different authentication techniques for RFID technologies, providing solutions to the following research issues: 1) detecting counterfeit as well as ensuring low response time in large scale RFID systems, 2) preserving privacy and maintaining scalability in RFID based healthcare systems, 3) ensuring security and survivability of Computational RFID (CRFID) networks, and 4) detecting missing WISP tags efficiently to ensure reliability of CRFID based system\u27s decision. The techniques presented in this dissertation achieve good levels of privacy, provide security, scale to large systems, and can be implemented on resource-constrained RFID devices

Integrated ZigBee RFID sensor networks for resource tracking and monitoring in logistics management

The Radio Frequency Identification (RFID), which includes passive and active systems and is the hottest Auto-ID technology nowadays, and the wireless sensor network (WSN), which is one of the focusing topics on monitoring and control, are two fast-growing technologies that have shown great potential in future logistics management applications. However, an information system for logistics applications is always expected to answer four questions: Who, What, When and Where (4Ws), and neither of the two technologies is able to provide complete information for all of them. WSN aims to provide environment monitoring and control regarded as When and What , while RFID focuses on automatic identification of various objects and provides Who (ID). Most people usually think RFID can provide Where at all the time. But what normal passive RFID does is to tell us where an object was the last time it went through a reader, and normal active RFID only tells whether an object is presenting on site. This could sometimes be insufficient for certain applications that require more accurate location awareness, for which a system with real-time localization (RTLS), which is an extended concept of RFID, will be necessary to answer Where constantly. As WSN and various RFID technologies provide information for different but complementary parts of the 4Ws, a hybrid system that gives a complete answer by combining all of them could be promising in future logistics management applications. Unfortunately, in the last decade those technologies have been emerging and developing independently, with little research been done in how they could be integrated. This thesis aims to develop a framework for the network level architecture design of such hybrid system for on-site resource management applications in logistics centres. The various architectures proposed in this thesis are designed to address different levels of requirements in the hierarchy of needs, from single integration to hybrid system with real-time localization. The contribution of this thesis consists of six parts. Firstly, two new concepts, Reader as a sensor and Tag as a sensor , which lead to RAS and TAS architectures respectively, for single integrations of RFID and WSN in various scenarios with existing systems; Secondly, a integrated ZigBee RFID Sensor Network Architecture for hybrid integration; Thirdly, a connectionless inventory tracking architecture (CITA) and its battery consumption model adding location awareness for inventory tracking in Hybrid ZigBee RFID Sensor Networks; Fourthly, a connectionless stochastic reference beacon architecture (COSBA) adding location awareness for high mobility target tracking in Hybrid ZigBee RFID Sensor Networks; Fifthly, improving connectionless stochastic beacon transmission performance with two proposed beacon transmission models, the Fully Stochastic Reference Beacon (FSRB) model and the Time Slot Based Stochastic Reference Beacon (TSSRB) model; Sixthly, case study of the proposed frameworks in Humanitarian Logistics Centres (HLCs). The research in this thesis is based on ZigBee/IEEE802.15.4, which is currently the most widely used WSN technology. The proposed architectures are demonstrated through hardware implementation and lab tests, as well as mathematic derivation and Matlab simulations for their corresponding performance models. All the tests and simulations of my designs have verified feasibility and features of our designs compared with the traditional systems

Towards machine learning enabled future-generation wireless network optimization

We anticipate that there will be an enormous amount of wireless devices connected to the Internet through the future-generation wireless networks. Those wireless devices vary from self-driving vehicles to smart wearable devices and intelligent house- hold electrical appliances. Under such circumstances, the network resource optimization faces the challenge of the requirement of both flexibility and performance. Current wireless communication still relies on one-size-fits-all optimization algorithms, which require meticulous design and elaborate maintenance, thus not flexible and cannot meet the growing requirements well. The future-generation wireless networks should be “smarter”, which means that the artificial intelligence-driven software-level design will play a more significant role in network optimization. In this thesis, we present three different ways of leveraging artificial intelligence (AI) and machine learning (ML) to design network optimization algorithms for three wireless Internet of things network optimization problems. Our ML-based approaches cover the use of multi-layer feed-forward artificial neural network and the graph convolutional network as the core of our AI decision-makers. The learning methods are supervised learning (for static decision-making) and reinforcement learning (for dynamic decision-making). We demonstrate the viability of applying ML in future- generation wireless network optimizations through extensive simulations. We summarize our discovery on the advantage of using ML in wireless network optimizations as the following three aspects: 1. Enabling the distributed decision-making to achieve the performance that near a centralized solution, without the requirement of multi-hop information; 2. Tackling with dynamic optimization through distributed self-learning decision- making agents, instead of designing a sophisticated optimization algorithm; 3. Reducing the time used in optimizing the solution of a combinatorial optimization problem. We envision that in the foreseeable future, AI and ML could help network service designers and operators to improve the network quality of experience swiftly and less expensively

Multiple zones surveillance system using RFID

Monitoring and tracking the activities of individuals (or objects) in multiple zones or areas simultaneously is quite a challenging task. It is a very common practice to use observation cameras or to have security personnel to guard the specified areas. However, area surveillances using these common methods may become tedious when the activities to watch out for increases. More cameras as well as manpower are needed to cater for the increment of activities for each zone. On top of that, should anyone (or objects) vacates or trespasses the designated areas, it would take some time to identify them, hence resulting complexity in tracing their whereabouts. To overcome these challenges, we propose a surveillance system for multiple zones using RFID technology. Individuals or objects to be monitored are tagged using RFID tags that hold unique identification. Each zone is allocated with one RFID reader, which will transmit the information of activities of the respective zones to the host computer in the control room. The security personnel in the control room would be able to identify which individual or objects that are out of their designated zones or trespassing to another zone based on the tags that has been detected by the reader. Should the tags are removed without authorization, alarm will be generated. Every activity transactions are recorded in a database for future references or actions. A case study of inmate tracking system is conducted and demonstrated to prove the capability of the proposed method