Abstract

A wireless medical sensor network (WMSN) is a professional application of the traditional wireless body area sensor networks in medicine. Using WMSNs, the parameters of patients’ vital signs can be gathered from the sensor nodes deployed on the body of the patients and accessed by the healthcare professionals by using a mobile device. Due to wireless communication, securing communication becomes a vital issue in WMSNs. Since the vital signs parameters are sensitive to the patients’ health status and these information must not be revealed to the others except the healthcare professionals, the protection of patients’ privacy becomes another key issue for WMSNs applications. Thus, user authentication with anonymity property is the most basic and commonly used method in order to resolve the security and privacy issues of WMSNs. He et al. presented a user authentication protocol for healthcare applications using WMSNs to protect the security and privacy problems. However, Li et al. showed that their scheme is incorrect in authentication and session key agreement phase, has no wrong password detection mechanism and is vulnerable to denial of service caused by password change with wrong password. In this paper, we review Li et al.’s scheme and show that their scheme is still vulnerable to privileged-insider attack, sensor node capture attack and fails to provide user anonymity property. Moreover, we find that He et al.’s scheme is still vulnerable to the same attacks as we find out in Li et al.’s scheme. In order to remedy the security weak-nesses found in both He et al.’s scheme and Li et al.’s scheme, we present a secure biometrics-based user authentication scheme in WMSNs using smart card. Through the rigorous formal and informal security analysis, we show that our scheme is secure against possible known attacks. In addition, we simulate our scheme using the most-widely accepted and used Automated Validation of Internet Security Protocols and Application stool and the simulation results reveal that our scheme is secure. Our scheme is also efficient in computation and communication as compared to He et al.’s scheme, Li et al.’sscheme and other related schemes.

Abstract

Rapid development of the wireless communication technology and low cost of sensing devices has accelerated the development of wireless sensor networks (WSNs). These types of networks have a wide range of applications including habitat monitoring, health monitoring, data acquisition in hazardous environmental conditions and military operations. Sensor nodes are resource constrained having limited communication range, battery and processing power. Sensor nodes are prone to failure and can be also physically captured by an adversary. One of the main concerns in WSNs is to provide security, especially in the cases where they are deployed for military applications and monitoring. Further, WSNs are prone to various attacks such as wormhole, sinkhole and blackhole attacks. A blackhole attack is a kind of denial of service attack, which is very difficult to detect and defend and such blackhole attack, if happens, affects the entire performance of the network. In addition, it causes high end-to-end delay and less throughput with less packet delivery ratio. The situation can be worst if multiple blackhole attacker nodes present in the network. As a result, detection and prevention of the blackhole attack becomes crucial in WSNs. In this paper, we aim to propose a new efficient group-based technique for the detection and prevention of multiple blackhole attacker nodes in WSNs. In our approach, the entire WSN is divided into several clusters and each cluster has a powerful high-end sensor node (called a cluster head), which is responsible for the detection of blackhole attacker nodes, if present, in that cluster. The proposed scheme achieves about 90 % detection rate and 3.75 % false positive rate, which are significantly better than the existing related schemes. Furthermore, our scheme is efficient and thus, it is very appropriate for practical applications in WSNs.

Abstract

Due to the rapid development of wireless communication systems, authentication becomes a key security component in smart grid environments. Authentication then plays an important role in the smart grid domain by providing a variety of security services including credentials' privacy, session-key (SK) security, and secure mutual authentication. In this paper, we analyze the security of a recent relevant work in smart grid, and it is unfortunately not able to deal with SK-security and smart meter secret credentials' privacy under the widely accepted Canetti-Krawczyk adversary (CK-adversary) model. We then propose a new efficient provably secure authenticated key agreement scheme for smart grid. Through the rigorous formal security analysis, we show that the proposed scheme achieves the well-known security functionalities including smart meter credentials' privacy and SK-security under the CK-adversary model. The proposed scheme reduces the computation overheads for both smart meters and service providers. Furthermore, the proposed scheme offers more security functionalities as compared to the existing related schemes.

Abstract

Sensor nodes in a wireless sensor network (WSN) may be lost due to enervation or malicious attacks by an adversary. WSNs deployed for several applications including military applications are prone to various attacks, which degrade the network performance very rapidly. Hybrid anomaly is a type of anomaly that contains the different types of attacker nodes such as blackhole, misdirection, wormhole etc. These multiple attacks can be launched in the network using the hybrid anomaly. In this situation, it is very difficult to find out which kind of attacker nodes are activated in the network. This motivates us to design a robust and efficient secure intrusion detection approach in order to extend thelifetime of a WSN. In this paper, we aim to propose a new intrusion detection technique forhybrid anomaly, which uses the existing data mining algorithm, called K-means clustering.For the detection purpose, patterns of intrusions are built automatically by the K-mean sclustering algorithm over training data. After that intrusions are detected by matching network activities against these detection patterns. We evaluate our approach over a WSNd ataset that is created using Opnet modeler, which contains various attributes, such as end-to-end delay, traffic sent and traffic received. The training data set contains the normal values of the network parameters. The testing dataset is created in actual working mode consists of normal and abnormal values of the network parameters. The proposed tech-nique has the ability to detect two types of malicious nodes: black hole and misdirection nodes. Our scheme achieves 98.6 % detection rate and 1.2 % false positive rate, which are significantly better than the existing related schemes.

Abstract

In recent years, high utility itemsets (HUIs) mining from the transactional databases becomes one of the most emerging research topic in the field of data mining due to its wide range of applications in online e-commerce data analysis, identifying interesting patterns in biomedical data and for cross marketing solutions in retail business. It aims to discover the itemsets with high utilities efficiently by considering item quantities in a transaction and profit values of each item. However, it produces a tremendous number of HUIs, which imposes further burden in analysis of the extracted patterns and also degrades the performance of mining methods. Mining the set of closed + high utility itemsets (CHUIs) solves this issue as it is a loss-less and condensed representation of all HUIs. In this paper, we aim to present a new algorithm for finding CHUIs from a transactional database, called the CHUM (Closed + High Utility itemset Miner), which is scalable and efficient. The proposed mining algorithm adopts a tricky aimed vertical representation of the database in order to speed up the execution time in generating itemset closures and compute their utility information without accessing the database. The proposed method makes use of the item co-occurrences strategy in order to further reduce the number of intersections needed to be performed. Several experiments are conducted on various sparse and dense datasets and the simulation results clearly show the scalability and superior performance of our algorithm as compared to those for the existing state-of-the-art CHUD (Closed + High Utility itemset Discovery) algorithm.

Abstract

User authentication is one of the most important security services required forthe resource-constrained wire-less sensor networks (WSNs). In user authentication, for critical applications of WSNs, a legitimate user is allowed to query and collect the real-time data at any time from a sensor node of the network as and when he/she demands for it. In order to get the real-time information from the nodes,the user needs to be first authenticated by the nodes as well as the gateway node (GWN) of WSN so that illegal accesst o nodes do not happen in the network. Recently, Jiang et al.proposed an efficient two-factor user authentication scheme with unlinkability property in WSNs Jiang (2014). In this paper, we analyze Jiang et al.’s scheme. Unfortunately, we point out that Jiang et al.’s scheme has still several draw-backs such as (1) it fails to protect privileged insider attack,(2) inefficient registration phase for the sensor nodes,(3) it fails to provide proper authentication in login and authentication phase, (4) it fails to update properly the new changed password of a user in the password update phase,(5) it lacks of supporting dynamic sensor node addition after initial deployment of nodes in the network, and (6) itlacks the formal security verification. In order to withstand these pitfalls found in Jiang et al.’s scheme, we aim to pro-pose a three-factor user authentication scheme for WSNs.Our scheme preserves the original merits of Jiang et al.’sscheme. Our scheme is efficient as compared to Jiang et al.’s

Abstract

The Session Initiation Protocol (SIP) is a signaling communications protocol, which has been chosen for controlling multimedia communication in 3G mobile networks. The proposed authentication in SIP is HTTP digest based authentication. Recently, Tu et al. presented an improvement of Zhang et al.’s smart card-based authenticated key agreement protocol for SIP. Their scheme efficiently resists password guessing attack. However, in this paper, we analyze the security of Tu et al.’s scheme and demonstrate their scheme is still vulnerable to user’s impersonation attack, server spoofing attack and man-in-the middle attack. We aim to propose an efficient improvement on Tu et al.’s scheme to overcome the weaknesses of their scheme, while retaining the original merits of their scheme. Through the rigorous informal and formal security analysis, we show that our scheme is secure against various known attacks including the attacks found in Tu et al.’sscheme. Furthermore, we simulate our scheme for the for-mal security analysis using the widely-accepted AVISPA(Automated Validation of Internet Security Protocols and Applications) tool and show that our scheme is secure against passive and active attacks including the replay and man-in-the-middle attacks. Additionally, the proposed scheme is comparable in terms of the communication and computational overheads with Tu et al.’s scheme and other related existing schemes.

Abstract

In tropical countries such as India, increasing the roof albedo helps to reduce the heat ingress through the roof. This further reduces air-conditioning energy consumption in conditioned buildings and increases comfort in unconditioned buildings. In order to help users determine the benefits of high albedo roofs under varying conditions, a simple calculator has been developed. Parameters such as location, building type, roof area, and surface properties of the roof are taken as inputs. Annual EnergyPlus simulations are performed for the given parameters and the results are displayed in both graphical and tabular formats. It also calculates the simple payback by comparing a given base case roof albedo with the proposed roof albedo. The calculator can perform comfort simulations for unconditioned buildings and simulates measures including a radiant barrier system and under deck roof insulation. The calculator also runs a parametric simulation between insulation thickness and roof albedo to find an optimum roof insulation thickness based on incremental internal rate of return. This paper presents the features of the cool roof calculator and the type of analysis that can be performed using the cached results.

Abstract

Increasing roof reflectance reduces absorption of solar radiation, roof surface temperature and heat ingress into the building. This leads to an increase in indoor comfort and reduction in room air temperature that in turn results in energy saving by reducing AC demand. To assess this impact of cool roofs on buildings in rural and peri-urban areas of India, a study was performed on two un-conditioned school buildings in Hyderabad (ZPH School) and Nagpur (VNHM School). Two classrooms of same size, function, and occupancy from both the school buildings were monitored for a period of ten weeks starting from March 2014 till May 2014. The data from the experiments and their analyses showed promising results. The average reduction and peak reduction in indoor air, roof underdeck and roof overdeck surface temperatures are 2.1 ◦C, 5.0 ◦C and 12.3 ◦C and 4.3 ◦C, 10.0 ◦C and 26.3 ◦C respectively for the room with white roof as opposed to grey roof in ZPH School and 1.5 ◦C, 4.0 ◦C and 9.5 ◦C, and 3.3 ◦C, 4.2 ◦C, and 25.2 ◦C respectively in VNHM School. The results from the experiment prove that white roof has a significant effect in reducing the indoor air temperatures in buildings due to reduction in outdoor and indoor roof surface temperature

Abstract

Selecting a high albedo (solar reflectance) waterproofing layer on the top of a roof helps lower the roof’s surface temperature and reduce the air conditioning energy consumption in the top floor of a building. The annual energy savings depend on factors including weather, internal loads, and building operation schedule. To demonstrate the energy saving potential of high albedo roofs, an apparatus consisting of two nearly identical test chambers (A and B) has been built in four Indian climates: Chennai (hot & humid), Bangalore (temperate), Jhagadia (Hot & dry) and Delhi (composite). Each chamber has well-insulated walls to mimic the core of an office building. Both chambers have the same construction, equipment, and operating schedule, differing only in roof surface. The reinforced cement concrete roof of Chamber A is surfaced with a low-albedo cement layer, while that of Chamber B is surfaced with a high-albedo water proof membrane (change in solar reflectance of 0.28). The experiment will be carried out for one year to explore seasonal variations in energy savings. Initial results in the month of July (post summer) shows that savings from high albedo roof ranges from 0.04 kWh/m2/day in temperate climates, to 0.08 kWh/m2/day in hot & dry climate.