Efficient threshold self-healing key distribution with sponsorization for infrastructureless wireless networks

Self-healing key distribution schemes are particularly useful when there is no network infrastructure or such infrastructure has been destroyed. A self-healing mechanism can allow group users to recover lost session keys and is therefore quite suitable for establishing group keys over an unreliable network, especially for infrastructureless wireless networks, where broadcast messages loss may occur frequently. An efficient threshold self-healing key distribution scheme with favorable properties is proposed in this paper. The distance between two broadcasts used to recover the lost one is alterable according to network conditions. This alterable property can be used to shorten the length of the broadcast messages. The second property is that any more than threshold-value users can sponsor a new user to join the group for the subsequent sessions without any interaction with the group manager. Furthermore, the storage overhead of the self-healing key distribution at each group user is a polynomial over a finite field, which will not increase with the number of sessions. In addition, if a smaller group of users up to a threshold-value were revoked, the personal keys for non-revoked users can be reused

Key management for wireless sensor network security

Wireless Sensor Networks (WSNs) have attracted great attention not only in industry but also in academia due to their enormous application potential and unique security challenges. A typical sensor network can be seen as a combination of a number of low-cost sensor nodes which have very limited computation and communication capability, memory space, and energy supply. The nodes are self-organized into a network to sense or monitor surrounding information in an unattended environment, while the self-organization property makes the networks vulnerable to various attacks.Many cryptographic mechanisms that solve network security problems rely directly on secure and efficient key management making key management a fundamental research topic in the field of WSNs security. Although key management for WSNs has been studied over the last years, the majority of the literature has focused on some assumed vulnerabilities along with corresponding countermeasures. Specific application, which is an important factor in determining the feasibility of the scheme, has been overlooked to a large extent in the existing literature.This thesis is an effort to develop a key management framework and specific schemes for WSNs by which different types of keys can be established and also can be distributed in a self-healing manner; explicit/ implicit authentication can be integrated according to the security requirements of expected applications. The proposed solutions would provide reliable and robust security infrastructure for facilitating secure communications in WSNs.There are five main parts in the thesis. In Part I, we begin with an introduction to the research background, problems definition and overview of existing solutions. From Part II to Part IV, we propose specific solutions, including purely Symmetric Key Cryptography based solutions, purely Public Key Cryptography based solutions, and a hybrid solution. While there is always a trade-off between security and performance, analysis and experimental results prove that each proposed solution can achieve the expected security aims with acceptable overheads for some specific applications. Finally, we recapitulate the main contribution of our work and identify future research directions in Part V

An efficient self-healing key distribution scheme

Self-healing key distribution schemes enable a group user to recover session keys from two broadcast messages he received before and after those sessions, even if the broadcast messages for the middle sessions are lost due to network failure. These schemes are quite suitable in supporting secure communication over unreliable networks such as sensor networks and ad hoc networks. An efficient self-healing key distribution scheme is proposed in this paper. The scheme bases on the concept of access polynomial and self-healing key distribution model constructed by Hong et al. The new scheme reduces communication and computation overheads greatly yet still keeps the constant storageoverhead

A self-healing key distribution scheme based on vector space secret sharing and one way hash chains

An efficient self-healing key distribution scheme with revocation capability is proposed for secure group communication in wireless networks. The scheme bases on vector space secret sharing and one way hash function techniques. Vector space secret sharing helps to realize general monotone decreasing structures for the family of subsets of users that can be revoked instead of a threshold one. One way hash chains contribute to reduce communication overhead. Furthermore, the most prominent characteristic of our scheme is resisting collusion between the new joined users and the revoked users, which is fatal weakness of hash function based self-healing key distribution schemes

A survey of machine learning techniques applied to self organizing cellular networks

In this paper, a survey of the literature of the past fifteen years involving Machine Learning (ML) algorithms applied to self organizing cellular networks is performed. In order for future networks to overcome the current limitations and address the issues of current cellular systems, it is clear that more intelligence needs to be deployed, so that a fully autonomous and flexible network can be enabled. This paper focuses on the learning perspective of Self Organizing Networks (SON) solutions and provides, not only an overview of the most common ML techniques encountered in cellular networks, but also manages to classify each paper in terms of its learning solution, while also giving some examples. The authors also classify each paper in terms of its self-organizing use-case and discuss how each proposed solution performed. In addition, a comparison between the most commonly found ML algorithms in terms of certain SON metrics is performed and general guidelines on when to choose each ML algorithm for each SON function are proposed. Lastly, this work also provides future research directions and new paradigms that the use of more robust and intelligent algorithms, together with data gathered by operators, can bring to the cellular networks domain and fully enable the concept of SON in the near future

Resilient Wireless Sensor Networks Using Topology Control: A Review

Wireless sensor networks (WSNs) may be deployed in failure-prone environments, and WSNs nodes easily fail due to unreliable wireless connections, malicious attacks and resource-constrained features. Nevertheless, if WSNs can tolerate at most losing k − 1 nodes while the rest of nodes remain connected, the network is called k − connected. k is one of the most important indicators for WSNs’ self-healing capability. Following a WSN design flow, this paper surveys resilience issues from the topology control and multi-path routing point of view. This paper provides a discussion on transmission and failure models, which have an important impact on research results. Afterwards, this paper reviews theoretical results and representative topology control approaches to guarantee WSNs to be k − connected at three different network deployment stages: pre-deployment, post-deployment and re-deployment. Multi-path routing protocols are discussed, and many NP-complete or NP-hard problems regarding topology control are identified. The challenging open issues are discussed at the end. This paper can serve as a guideline to design resilient WSNs

The effect of time dimension and network dynamics on key distribution in wireless sensor networks

The majority of studies on security in resource limited wireless sensor networks (WSN) focus on finding an efficient balance among energy consumption, computational speed and memory usage. Besides these resources, time, network dynamics (e.g. routing), and implementation and integration issues of the security solutions are relatively immature aspects that can be considered in system design and performance evaluations. In the first part of this thesis, we develop and analyze different implementation options of a Random Key Predistribution scheme in a real network simulation environment. Implementation options include Proactive Key Establishment and Reactive Key Establishment. In Proactive Key Establishment, pairwise keys are established at the beginning, prior to start of application. In Reactive Key Establishment, keys are established only whenever needed by the application during its execution. In literature the latter is known to preserve energy since it reduces useless key establishments; however, it also introduces delay in application traffic. We implement the reactive key establishment in such a way that key establishment traffic and energy consumption are reduced. As a result our reactive key establishment implementation has similar throughput performance with proactive scenarios despite the longer lifetime of reactive scenario. We also simulate an attack scenario and measure different metrics including a novel one. This new metric, the packet compromise ratio, reflects the harm caused by the adversary in a more realistic way. In our simulations, we show that packet compromise ratios are very high as compared to link compromise ratios for a long period. However, when the majority of nodes die, link compromise ratios exceed packet compromise ratios. This is an indication to the fact that link compromise ratios seem high even though there is no high amount of traffic in network to be compromised by adversary. Due to the results showing that classical key distribution schemes in WSNs have actually low resiliency, in the second part of this thesis, we propose new deployment models that improve resiliency. In a recent study by Castelluccia and Spognardi, the time dimension is used to lower the ratio of compromised links, thus, improving resiliency in key distribution in WSNs. This is achieved by making the old and possibly compromised keys useful only for a limited amount of time. In this way, the effect of compromised keys diminishes in time, so the WSN selfheals. We further manipulate the time dimension and propose a deployment model that speeds up the resiliency improvement process with a tradeo between connectivity and resiliency. In our method, self healing speeds up by introducing nodes that belong to future generations in the time scale. In this way, the duration that the adversary can make use of compromised keys becomes smaller

Immune System Based Control and Intelligent Agent Design for Power System Applications

The National Academy of Engineering has selected the US Electric Power Grid as the supreme engineering achievement of the 20th century. Yet, this same grid is struggling to keep up with the increasing demand for electricity, its quality and cost. A growing recognition of the need to modernize the grid to meet future challenges has found articulation in the vision of a Smart Grid in using new control strategies that are intelligent, distributed, and adaptive. The objective of this work is to develop smart control systems inspired from the biological Human Immune System to better manage the power grid at the both generation and distribution levels. The work is divided into three main sections. In the first section, we addressed the problem of Automatic Generation Control design. The Clonal Selection theory is successfully applied as an optimization technique to obtain decentralized control gains that minimize a performance index based on Area Control Errors. Then the Immune Network theory is used to design adaptive controllers in order to diminish the excess maneuvering of the units and help the control areas comply with the North American Electric Reliability Corporation\u27s standards set to insure good quality of service and equitable mutual assistance by the interconnected energy balancing areas. The second section of this work addresses the design and deployment of Multi Agent Systems on both terrestrial and shipboard power systems self-healing using a novel approach based on the Immune Multi-Agent System (IMAS). The Immune System is viewed as a highly organized and distributed Multi-Cell System that strives to heal the body by working together and communicating to get rid of the pathogens. In this work both simulation and hardware design and deployment of the MAS are addressed. The third section of this work consists in developing a small scale smart circuit by modifying and upgrading the existing Analog Power Simulator to demonstrate the effectiveness of the developed technologies. We showed how to develop smart Agents hardware along with a wireless communication platform and the electronic switches. After putting together the different designed pieces, the resulting Multi Agent System is integrated into the Power Simulator Hardware. The multi Agent System developed is tested for fault isolation, reconfiguration, and restoration problems by simulating a permanent three phase fault on one of the feeder lines. The experimental results show that the Multi Agent System hardware developed performed effectively and in a timely manner which confirms that this technology is very promising and a very good candidate for Smart Grid control applications