Key Management in Wireless Sensor Networks, IP-Based Sensor Networks, Content Centric Networks

Cryptographic keys and their management in network communication is considered the main building block of security over which other security primitives are based. These cryptographic keys ensure the privacy, authentication, integrity and non-repudiation of messages. However, the use of these cryptographic keys and their management in dealing with the resource constrained devices (i.e. Sensor nodes) is a challenging task. A number of key management schemes have been introduced by researchers all over the world for such resource constrained networks. For example, light weight PKI and elliptic curve cryptography schemes are computationally expensive for these resource constrained devices. So far the symmetric key approach is considered best for these constrained networks and different variants of it been developed for these networks (i.e. probabilistic key distribution approach). The probabilistic key distribution approach consumes less memory than the standard symmetric key approach but it suffers from the connectivity issues (i.e. the connectivity depends on the common shared keys between the nodes). Most of those schemes were proposed by considering static sensor networks (e.g. Industrial process monitoring, Environmental monitoring, movement detection in military applications, forests etc.). However, the use of these existing key management schemes for mobile wireless sensor networks applications introduces more challenges in terms of network connectivity, energy consumption, memory cost, communication overhead and protection of key materials against some well known attacks. Keeping these challenges in mind, previous research has proposed some key management schemes considering the mobility scenarios in ad hoc networks and wireless sensor networks (e.g. vehicular networks, health monitoring systems).However these schemes consume more resource because of a much higher communication packet exchange during the handover phase for the authentication of joining and leaving nodes than the static networks where there is no extra communication for the handover and authentication. The motivation of this research work is to investigate and propose new algorithms not only to improve the efficiency of these existing authentication and key management schemes in terms of connectivity, memory and security by considering the mobility scenario in wireless sensor networks, but also to develop new algorithms that suit these constrained networks than the existing schemes. First, we choose the existing key pool approach for authentication and key management and improve its network connectivity and resilience against some well known attacks (e.g. node capturing attacks) while reduce the memory cost by storing those key pools in each sensor node. In the proposed solution, we have divided the main key pool into two virtual mutually exclusive key pools. This division and constructing a key from two chosen keys, one from each key pool, helps to reduce the memory cost of each node by assigning fewer keys for the same level of network connectivity as the existing key pool frameworks. Although, the proposed key pool approach increases the network resilience against node compromission attacks because of the smaller number of keys assigned to each node, however it does not completely nullify the effect of the attacks. Hence we proposed an online mutual authentication and key establishment and management scheme for sensor networks that provides almost 100\% network connectivity and also nullifies the effect of node compromission attacks. In the proposed online key generation approach, the secret key is dependent on both communicating parties. Once the two communicating parties authenticate each other, they would successfully establish a secret communication key, otherwise they stop communication and inform the network manager about the intruder detection and activity. The last part of the thesis considers the integration of two different technologies (i.e. wireless sensor networks and IP networks). This is a very interesting and demanding research area because of its numerous applications, such as smart energy, smart city etc.. However the security requirements of these two kind of networks (resource constrained and resourceful) make key management a challenging task. Hence we use an online key generation approach using elliptic curve cryptography which gives the same security level as the standard PKI approach used in IP networks with smaller key length and is suited for the sensor network packet size limitations. It also uses a less computationally expensive approach than PKI and hence makes ECC suitable to be adopted in wireless sensor networks. In the key management scheme for IP based sensor networks, we generate the public private key pair based on ECC for each individual sensor node. However the public key is not only dependent on the node's parameter but also the parameters of the network to which it belongs. This increases the security of the proposed solution and avoids intruders pretending to be authentic members of the network(s) by spreading their own public keys. In the last part of the thesis we consider Content Centric Networking (CCN) which is a new routing architecture for the internet of the future. Building on the observation that today's communications are more oriented towards content retrieval (web, P2P, etc.) than point-to-point communications (VoIP, IM, etc.), CCN proposes a radical revision of the Internet architecture switching from named hosts (TCP/IP protocols) to named data to best match its current usage. In a nutshell, content is addressable, routable, self-sufficient and authenticated, while locations no longer matter. Data is seen and identified directly by a routable name instead of a location (the address of the server). Consequently, data is directly requested at the network level not from its holder, hence there is no need for the DNS). To improve content diffusion, CCN relies on data distribution and duplication, because storage is cheaper than bandwidth: every content - particularly popular one - can be replicated and stored on any CCN node, even untrustworthy. People looking for particular content can securely retrieve it in a P2P-way from the best locations available. So far, there has been little investigation of the security of CCNs and there is no specific key management scheme for that. We propose an authentication and key establishment scheme for CCNs in which the contents are authenticated by the content generating node, using pre-distributed shares of encryption keys. The content requesting node can get those shares from any node in the network, even from malicious and intruder ones, in accordance with a key concept of CCNs. In our work we also provide means to protect the distributed shares from modification by these malicious/intruder nodes. The proposed scheme is again an online key generation approach but including a relation between the content and its encryption key. This dependency prevents the attackers from modifying the packet or the key shares

Key Management in Wireless Sensor Networks, IP-Based Sensor Networks, Content Centric Networks

Cryptographic keys and their management in network communication is considered the main building block of security over which other security primitives are based. These cryptographic keys ensure the privacy, authentication, integrity and non-repudiation of messages. However, the use of these cryptographic keys and their management in dealing with the resource constrained devices (i.e. Sensor nodes) is a challenging task. A number of key management schemes have been introduced by researchers all over the world for such resource constrained networks. For example, light weight PKI and elliptic curve cryptography schemes are computationally expensive for these resource constrained devices. So far the symmetric key approach is considered best for these constrained networks and different variants of it been developed for these networks (i.e. probabilistic key distribution approach). The probabilistic key distribution approach consumes less memory than the standard symmetric key approach but it suffers from the connectivity issues (i.e. the connectivity depends on the common shared keys between the nodes). Most of those schemes were proposed by considering static sensor networks (e.g. Industrial process monitoring, Environmental monitoring, movement detection in military applications, forests etc.). However, the use of these existing key management schemes for mobile wireless sensor networks applications introduces more challenges in terms of network connectivity, energy consumption, memory cost, communication overhead and protection of key materials against some well known attacks. Keeping these challenges in mind, previous research has proposed some key management schemes considering the mobility scenarios in ad hoc networks and wireless sensor networks (e.g. vehicular networks, health monitoring systems).However these schemes consume more resource because of a much higher communication packet exchange during the handover phase for the authentication of joining and leaving nodes than the static networks where there is no extra communication for the handover and authentication. The motivation of this research work is to investigate and propose new algorithms not only to improve the efficiency of these existing authentication and key management schemes in terms of connectivity, memory and security by considering the mobility scenario in wireless sensor networks, but also to develop new algorithms that suit these constrained networks than the existing schemes. First, we choose the existing key pool approach for authentication and key management and improve its network connectivity and resilience against some well known attacks (e.g. node capturing attacks) while reduce the memory cost by storing those key pools in each sensor node. In the proposed solution, we have divided the main key pool into two virtual mutually exclusive key pools. This division and constructing a key from two chosen keys, one from each key pool, helps to reduce the memory cost of each node by assigning fewer keys for the same level of network connectivity as the existing key pool frameworks. Although, the proposed key pool approach increases the network resilience against node compromission attacks because of the smaller number of keys assigned to each node, however it does not completely nullify the effect of the attacks. Hence we proposed an online mutual authentication and key establishment and management scheme for sensor networks that provides almost 100\% network connectivity and also nullifies the effect of node compromission attacks. In the proposed online key generation approach, the secret key is dependent on both communicating parties. Once the two communicating parties authenticate each other, they would successfully establish a secret communication key, otherwise they stop communication and inform the network manager about the intruder detection and activity. The last part of the thesis considers the integration of two different technologies (i.e. wireless sensor networks and IP networks). This is a very interesting and demanding research area because of its numerous applications, such as smart energy, smart city etc.. However the security requirements of these two kind of networks (resource constrained and resourceful) make key management a challenging task. Hence we use an online key generation approach using elliptic curve cryptography which gives the same security level as the standard PKI approach used in IP networks with smaller key length and is suited for the sensor network packet size limitations. It also uses a less computationally expensive approach than PKI and hence makes ECC suitable to be adopted in wireless sensor networks. In the key management scheme for IP based sensor networks, we generate the public private key pair based on ECC for each individual sensor node. However the public key is not only dependent on the node's parameter but also the parameters of the network to which it belongs. This increases the security of the proposed solution and avoids intruders pretending to be authentic members of the network(s) by spreading their own public keys. In the last part of the thesis we consider Content Centric Networking (CCN) which is a new routing architecture for the internet of the future. Building on the observation that today's communications are more oriented towards content retrieval (web, P2P, etc.) than point-to-point communications (VoIP, IM, etc.), CCN proposes a radical revision of the Internet architecture switching from named hosts (TCP/IP protocols) to named data to best match its current usage. In a nutshell, content is addressable, routable, self-sufficient and authenticated, while locations no longer matter. Data is seen and identified directly by a routable name instead of a location (the address of the server). Consequently, data is directly requested at the network level not from its holder, hence there is no need for the DNS). To improve content diffusion, CCN relies on data distribution and duplication, because storage is cheaper than bandwidth: every content - particularly popular one - can be replicated and stored on any CCN node, even untrustworthy. People looking for particular content can securely retrieve it in a P2P-way from the best locations available. So far, there has been little investigation of the security of CCNs and there is no specific key management scheme for that. We propose an authentication and key establishment scheme for CCNs in which the contents are authenticated by the content generating node, using pre-distributed shares of encryption keys. The content requesting node can get those shares from any node in the network, even from malicious and intruder ones, in accordance with a key concept of CCNs. In our work we also provide means to protect the distributed shares from modification by these malicious/intruder nodes. The proposed scheme is again an online key generation approach but including a relation between the content and its encryption key. This dependency prevents the attackers from modifying the packet or the key share

Achieving Energy Saving through Proxying Applications on behalf of Idle Devices

AbstractSeveral studies in the past have revealed that network end user devices are left powered up 24/7 even when idle just for the sake of maintaining Internet connectivity. Network devices normally support low power states but are kept inactive due to their inability to maintain network connectivity. The Network Connectivity Proxy (NCP) has recently been proposed as an effective mechanism to impersonate network connectivity on behalf of high power devices and enable them to sleep when idle without losing network presence. The NCP can efficiently proxy basic networking protocol, however, proxying of Internet based applications have no absolute solution due to dynamic and non-predictable nature of the packets they are sending and receiving periodically. This paper proposes an approach for proxying Internet based applications and presents the basic software architectures and capabilities. Further, this paper also practically evaluates the proposed framework and analyzes expected energy savings achievable under- different realistic conditions

Design and Implementation of UPnP-based Energy Gateway for Demand Side Management in Smart Grid

Legacy electrical grids are urged to evolve towards smart grids, the smarter power delivery system that relies heavily on ICT. Numerous smart grids applications are expected to be developed for efficient management and utilization of electricity at the demand side such as home automation, Advanced Metering Infrastructure (AMI), dynamic energy pricing, efficient load management, etc. For easing and boosting the development of new demand side services, the concept of Home Energy Gateway (HEG) has recently been proposed in literature. It involves communication with the utility as well as with devices at the consumer sites. The literature still lacks a comprehensive HEG design that could provide all essential features such as zero-configuration, auto-discovery, seamless plug & play communication, interoperability and integration, customers privacy and communication security.This paper addresses the HEG challenges in an effective way through the design of suitable communication frameworks and a security mechanism for enabling strong protection against cyber attacks. The proposed system effectively copes with the interoperability and integration issues between plethora of heterogeneous devices at the consumer sites. The devices in proposed system inherit plug & play features and support zero-configuration and seamless networking. Further, the proposed system design is technology-agnostic and flexible enough to be adopted for the implementation of any specific demand side service. This paper also evaluates the proposed system in real-networking environment and presents performance metrics

Localization performance evaluation of extended kalman filter in wireless sensors network

This paper evaluates the positioning and tracking performance of Extended Kalman Filter (EKF) in wireless sensors network. The EKF is a linear approximation of statistical Kalman Filter (KF) and has the capability to work efficiently in non-linear systems. The EKF is based on an iterative process of estimating current state information from the previously estimated state. Its working is based on the linearization of observation model around the mean of current state information. The EKF has small computation complexity and requires low memory compared to other Bayesian algorithms which makes it very suitable for low powered mobile devices. This paper evaluates the localization and tracking performance of EKF for (i) Position (P) model, (ii) Position-Velocity (PV) model and (iii) Position-Velocity-Acceleration (PVA) model. The EKF processes distance measurements from cricket sensors that are acquired through time difference of arrival between ultrasound and Radio Frequency (RF) signals. Further, localization performance under varying number of beacons/sensors is also evaluated in this paper. © 2014 Published by Elsevier B.V.Peer ReviewedPostprint (published version

Application of linear and nonlinear control schemes for the stability of smart grid

Reliability and controls are essential for preventing outages, load disparity, and synchronization mismatch in a power system. Smart Grid (SG) is a cost-effective solution for minimizing inter-regional variations, optimizing load demand, stabilizing equipment operations, and managing conventional and renewable power sources. However, SGs are still in their infancy, and abrupt changes in demand, grid disruptions, and weather-related variations in renewable energy have a significant impact on their stability. Various hardware and software controls are designed to preserve the stability of SG systems during disturbances and uncertainty. This paper examines the various forms of power system disturbances and their impacts on SG stability. In addition, an overview of the most common linear and nonlinear control strategies applied to SG systems is provided. Finally, advantages, disadvantages, and applications are discussed to highlight the need for more robust operational and control approaches to enhancing SG stability

EFFECTIVENESS OF RESPIRATORY MUSCLE TRAINING FOR PULMONARY FUNCTION IN POST OPERATIVE PATIENTS

Introduction: In cardiopulmonary respiratory muscles plays a vital role which is mostly affected in postoperative patients and leads to further respiratory complications. Training of respiratory muscles is important to improve the respiratory health status so that the threat of respiratory complications is reduced. This review aims to see whether it is effective to improve pulmonary function in postoperative patients. Material & Methods: Literature for this review was searched by using databases like PubMed, Pedro, Cochrane, and google scholar. In this review the included articles were published between 2010 to 2020. All RCT articles were included in this review showing results regarding the effectiveness of the respiratory muscle technique. Results: The review comprises 6 studies all of which show that the respiratory muscle technique is effective. Conclusion: In order to improve the pulmonary function of postoperative patient’s respiratory muscle training is effective

The impact of different biochars on Stemphylium leaf blight SLB suppression and productivity of onion Allium cepa L.

Objectives: Onion is a highly consumed vegetable crop in many countries, being a vital component of every dish. Recent studies indicated that different plant residues’ and animal manure-based biochars have strong impacts on the growth and development of plants. However, the impact of these biochars on disease suppression remains elusive. Therefore, this two-year study assessed the impact of animal and plant residues-based biochars on the suppression of Stemphylium leaf blight (SLB) of onion and productivity of the crop. Methods: Three pyrolyzed biochars cotton sticks, wheat straw and poultry litter) were used in the study. Biochars were prepared in the laboratory and applied to soil prior to crop sowing in same concentration during both years of study. Results: Poultry litter biochar had the highest impact on allometric traits and productivity of onion, and successfully reduced SLB severity. The control treatment had the lowest productivity and the highest disease severity during both years of the study. The remaining biochars (cotton sticks and wheat straw) hadmoderate influence on growth and development of onion plants. The disease severity was higher compared to poultry litter; however, it was lower in both biochars than control treatment. It is concluded that different animal and plant residues-based biochars could be used to improve plant health. Nonetheless, the response of these biochars will be crop-specific. Conclusion: Poultry litter biochar can be successfully used to suppress SLB in onion and productivity of the crop. Nevertheless, the actual mechanisms involved in disease suppression warrant further investigation