Babar Shah

Security analysis of IoT protocols: A focus in CoAP

Internet of things (IoT) or Web of Things (WoT) is a wireless network between smart products or smart things connected to the internet. It is a new and fast developing market which not only connects objects and people but also billions of gadgets and smart devices. With the rapid growth of IoT, there is also a steady increase in security vulnerabilities of the linked objects. For example, a car manufacturer may want to link the systems within a car to smart home network networks to increase sales, but if all the various people involved do not embrace security the system will be exposed to security risks. As a result, there are several new published protocols of IoT, which focus on protecting critical data. However, these protocols face challenges and in this paper, numerous solutions are provided to overcome these problems. The widely used protocols such as, 802.15.4, 6LoWPAN, and RPL are the resenting of the IoT layers PHY/MAC, Adoption and Network. While CoAP (Constrained Application Protocol) is the application layer protocol designed as replication of the HTTP to serve the small devices coming under class 1 and 2. Many implementations of CoAP has been accomplished which indicates its crucial amd upcoming role in the future of IoT applications. This research article explored the security of CoAP over DTLS incurring many issues and proposed solutions as well as open challenges for future research.

Towards Enhanced Searching Architecture for Unstructured Peer-to-Peer Over Mobile Ad Hoc Networks

With the rapid growth of individual mobile devices, the researchers are facing new challenges to deploy unstructured peer-to-peer (P2P) applications over mobile ad hoc networks (MANETs). Empirical studies indicates that although P2P and MANETs have similar preferences, but the resultant networks are not performing efficient and effective searching due to peer discovery, connectivity and mobility problems. To resolve these issues, the existing techniques mostly rely on flooding and random walks in P2P over MANETs to discover object of interest and thus introduce incredible network traffic. Thus, this article proposes Gnutella like unstructured P2P network to better meets the mobility requirement of ad hoc networks to optimize search performance. The proposed system presents a novel cache optimization technique and enhances ultrapeer selection scheme to make communication more efficient between peers and ultrapeer. Furthermore for quick and efficient search, we explore a novel jumping multiple walkers random walk approach with controlled replication. The proposed search mechanism not only reduces the effective query search time but also remarkably reduce network overhead. We validate our analysis and compare our proposal to competing protocols in simulations. Simulation results show that proposed scheme gives better performance than the competing protocols in terms of (1) the successful ratio of resolving a query, (2) the time and hop count of routing a query message, (3) the message overhead, and (4) average message response time.

Fuzzy Logic-Based Guaranteed Lifetime Protocol for Real-Time Wireless Sensor Networks.

Few techniques for guaranteeing a network lifetime have been proposed despite its great impact on network management. Moreover, since the existing schemes are mostly dependent on the combination of disparate parameters, they do not provide additional services, such as real-time communications and balanced energy consumption among sensor nodes; thus, the adaptability problems remain unresolved among nodes in wireless sensor networks (WSNs). To solve these problems, we propose a novel fuzzy logic model to provide real-time communication in a guaranteed WSN lifetime. The proposed fuzzy logic controller accepts the input descriptors energy, time and velocity to determine each node’s role for the next duration and the next hop relay node for real-time packets. Through the simulation results, we verified that both the guaranteed network’s lifetime and real-time delivery are efficiently ensured by the new fuzzy logic model. In more detail, the above-mentioned two performance metrics are improved up to 8%, as compared to our previous work, and 14% compared to existing schemes, respectively.

A Survey on Three-Dimensional Wireless Ad Hoc and Sensor Networks

In parallel with steady research and development in ad hoc and wireless sensor networks, many testbeds have been implemented and deployed in real world. Furthermore, some research works have addressed design issues for deployment in three-dimensional space such as sky or ocean. Since many research challenges in three-dimensional spaces have not been explored yet as much as two dimensional spaces, it is required to define the challenging tasks to provide reliable communication in three-dimensional space. In this survey, we aim to identify the unique properties of communication environments in three-dimensional space and address the overview of the state of the art in this research area. To achieve this, the survey is organized according to two good example networks, airborne ad hoc networks (AANETs) and underwater wireless sensor networks (UWSNs). For each network, we introduce and review the related research works to focus on infrastructure, localization, topology design, and position-based routing. Finally, open research issues are also discussed and presented.

Fuzzy Search Controller in Unstructured Mobile Peer-to-Peer Networks

Typical mobile P2P protocols largely relied on inflexible techniques such as, flooding, replicating, random walks and selective forwarding to route queries and discover objects of interest, which incur a relatively high search time due to remarkable network traffic, multiple copies and duplication of query messages. Recently proposed P2P protocols are able to reduce search time but due to peer mobility, these protocols cause low hit rate and high overhead. Thus, this article proposes novel fuzzy controller based probabilistic walk for unstructured mobile P2P networks to reduce search time. The search time is reduced by jumping a query walker to 2-hop away selected ultrapeer through fuzzy controller. Furthermore, each ultrapeer share its pong cache with its directly connected ultrapeer to increase hit rate and reduce network overhead. Simulations show that the fuzzy search controller gives better performance than the competing protocols in terms of reducing response time by 10% and increasing hit rate by 15% in different mobility scenarios.

An architecture for (m, k)-firm real-time streams in wireless sensor networks

Despite increasing demand of application specific requirements in wireless sensor networks, lots of research is still going on under assumption of general requirement without considering specific traffic model as well as several constraints. To address this issue, we have already introduced a new real-time application with (m, k)-firm model and developed communication protocols for multimedia sensor networks. But, scalability problem and lack of architecture for (m, k)-firm stream are major research challenges that remain unsolved. Based on corresponding demands, in this paper, we propose a new integrated architecture for (m, k)-firm stream in wireless sensor networks with following functions, that is, flow aggregation based on compositional hierarchical model, velocity based routing protocol, hybrid medium access control protocol, and congestion control scheme. Simulation results are given to prove the suitability of the architecture and performance improvement under several scenarios.

Context Mining of Sedentary Behaviour for Promoting Self-Awareness Using a Smartphone

Sedentary behaviour is increasing due to societal changes and is related to prolonged periods of sitting. There is sufficient evidence proving that sedentary behaviour has a negative impact on people’s health and wellness. This paper presents our research findings on how to mine the temporal contexts of sedentary behaviour by utilizing the on-board sensors of a smartphone. We use the accelerometer sensor of the smartphone to recognize user situations (i.e., still or active). If our model confirms that the user context is still, then there is a high probability of being sedentary. Then, we process the environmental sound to recognize the micro-context, such as working on a computer or watching television during leisure time. Our goal is to reduce sedentary behaviour by suggesting preventive interventions to take short breaks during prolonged sitting to be more active. We achieve this goal by providing the visualization to the user, who wants to monitor his/her sedentary behaviour to reduce unhealthy routines for self-management purposes. The main contribution of this paper is two-fold: (i) an initial implementation of the proposed framework supporting real-time context identification; (ii) testing and evaluation of the framework, which suggest that our application is capable of substantially reducing sedentary behaviour and assisting users to be active.

Tracking the sedentary lifestyle using smartphone: A pilot study

Smartphone is most ubiquitous device and provides unique opportunity of continuous and automated tracking of sedentary lifestyle with the help of embedded sensors. In this paper, we present the evaluation of our pilot study results to track the sedentary lifestyle. The proposed model works well in real-time and inside the smartphone environment to process the sensory data. We compute the time and frequency domain features over the acceleration signals and classify the context with non-parametric nearest neighbor algorithm. To analyze the lifestyle patterns, information is transferred to the cloud server for archiving, further computation and its availability anywhere, anytime for visualization. It facilitates users to maintain and monitor their everyday lifestyle patterns and assists them to change their unhealthy sedentary behaviour identified by the proposed research. Furthermore, achieved results demonstrate the applicability of the proposed research in real-world scenarios.

Micro-context recognition of sedentary behaviour using smartphone

Embedded sensors of smartphone provides a unique opportunity to recognize the micro-context of sedentary behaviour. In this paper, we present our research findings on how to recognize micro-contexts by utilizing on board sensors of smartphone. Our proposed approach consists of two stages process. First, we recognize the situation of a person to be either stationery or moving. If stationary, then high probability to be sedentary, in which we can then find micro details about the current context. Second, we process environmental sound and recognize the persons micro-context such as watching television, working on computers or relaxing. Furthermore, we also provide the lifestyle analytics over cloud computing infrastructure to make it available anywhere and anytime for self-management purpose. We developed an initial working prototype to evaluate the applicability of our approach in a real-world scenario.

A New Real-Time and Guaranteed Lifetime Protocol in Wireless Sensor Networks

Real-time applications are time and event critical, therefore they have strict constraint on delay, packet loss, and energy consumption in many wireless sensor networks (WSNs) scenarios, which demands the network to continue QoS operations for a preconfigured lifetime. Due to the scarce energy constraint sensor nodes in WSNs, guaranteed network lifetime is more desirable than unpredictable and uncertain prolonged lifetime. However, in spite of its importance and necessity in WSNs real-time deployment, no research work has been proposed to solve this complex problem. In this paper, we present a new centralized energy and coverage aware node scheduling scheme for WSNs to analyze energy usage as well as balancing energy consumption among nodes to survive for the preconfigured lifetime. Furthermore, the scheduling algorithm is extended to provide real-time routing by adjusting dynamic transmission range according to current energy state of a sensor node. Thus, the energy and coverage aware scheduling with dynamic range forwarding enables the unreliable WSNs to accomplish real-time routing for a guaranteed network lifetime. Simulation results show that the proposed scheme can achieve a 10% increase in real-time packets meeting their deadline and a significantly longer guaranteed network lifetime than protocols reported in the literature.