Novel Cross Optimization based Trusted and Opportunistic Routing Scheme in Wireless Sensor Network

Opportunistic routing in wireless networks under mobile computing domain is one of the point of attraction for the research. Consistency along with routing security are the challenges faced by many old schemes which results performance to be compromised. However the existing techniques developed for effective routing are cost effective without the concern for the exact positioning of nodes in the network but while designing the scheme, security still requires attention. A novel cross optimization based trusted and opportunistic routing scheme for WSN is proposed in this paper which is referred as Unified Trusted and Optimized Routing (UTOR) scheme. The prime intention of UTOR is to realize optimized data movement along with routing and data security. UTOR functions in two stages, the first stage recognizes and unites the unified nodes depending on defined liberal constant(LC) which has definite trust,  link stability, and quality components. Definite trust as well as link stability can be measured directly but time to live and the associated delay are considered for measuring the quality. Whereas in second stage optimized nodes selection takes place with the help of proposed UTOR over defined proclivity function(PF) based on definite_trust(DT), link_stability (LS), quality_of_node(QN) and distance. Proposed UTOR’s performance is evaluated based on performance measures for Ad-Hoc sensor network of varying range of dynamic nodes in the presence of black_hole and DoS attacks. UTOR exposes relatively superior throughput and detection rate at the same time showcases minimal distance and delay, which are comparatively better than competing schemes. Significantly higher throughput and detection_rate as 44.1 and 55.7 respectively alongside low distance and delay as 168.2 and 13 are shown by UTOR which are comparatively better performance parameters than competing schemes. UTOR’s effective use in WSN may be under real-time scenarios such as environmental monitoring, smart farming, automation industries etc

A Study of Energy-efficient Routing Supporting Coordinated Sleep Scheduling in Wireless Ad Hoc Networks

A wireless ad hoc network is a collection of wireless computing devices that self-configure to form a network independently of any fixed infrastructure. Many wireless ad hoc network devices such as smartphones and tablets are usually powered by batteries with a limited operation time. This poses a significant challenge to the design of low-power network protocols. On one hand, energy-efficient routing protocols are widely discussed to reduce the end-to-end transmission energy by controlling the transmission power at senders. Recently, opportunistic routing (OR) has attracted a lot of attention for maximizing energy efficiency by exploiting the gains of multi-receiver diversity. On the other hand, sleep scheduling is commonly adopted as an effective mechanism to further reduce power wasted in overhearing and idle listening. However, the prior work has mainly treated energy-efficient routing and sleep scheduling as two separate tasks, which leads to a serious problem that neither component can fully minimize the network-wide energy consumption. In this thesis, we study how energy-efficient routing can be coordinated with sleep scheduling to increase network-side energy efficiency. We identify a trade-off between the decreased transmit power at senders due to multi-receiver diversity and the increased power at forwarders with the incorporation of coordinated sleep scheduling. Moreover, we provide a comprehensive evaluation of coordinated sleep scheduling impact on energy-efficient routing performance based on a 2-D grid topology and time division multiple access (TDMA) medium access control (MAC). Extensive simulation results demonstrate the effectiveness of the integrated function of coordinated sleep scheduling, significant impact of coordinated sleep scheduling on the energy-efficient routing performance and relationship between the network conditions (in terms of the traffic load and node density) and overall system performance achieved by different energy-efficient routing protocols

Exploring Link Correlation for Performance Improvements in Wireless Networks

University of Minnesota Ph.D. dissertation. February 2017. Major: Computer Science. Advisor: Tian He. 1 computer file (PDF); x, 96 pages.In wireless communication, many technologies, such as Wi-Fi, BlueTooth and ZigBee, operate in the same ISM band. With the exponential growth of wireless devices, the ISM band becomes more and more crowded. These wireless devices compete with each other to access spectrum resources, generating cross-technology interference (CTI). Since cross-technology interference may destroy wireless communication, the field is facing an urgent and challenging need to investigate the packet reception quality of wireless links under CTI. In this dissertation, we propose an in-depth systematic study from empirical measurement, theoretical analysis, modeling, to design and implementation of protocols that exploit packet reception patterns of wireless links under cross-technology interference. Based on extensive measurements, we exploit link correlation phenomenon that packet receptions from a transmitter to multiple receivers are correlated. We then propose link correlation model which contradicts the widely made link independent assumption. The proposed model has a broad impact on network designs that utilize concurrent wireless links, which include (i) traditional network protocols such as broadcast, and (ii) diversity-based protocols such as network coding and opportunistic routing. In the study of the impact of link correlation model on traditional network protocols, we present the design and implementation of CorLayer, a general supporting layer for energy efficient reliable broadcast that carefully blacklists certain poorly correlated wireless links. We integrate CorLayer transparently with sixteen state-of-the-art broadcast protocols specified in thirteen publications on three physical testbeds running TelosB, MICAz, and GreenOrbs nodes, respectively. The experimental results show that CorLayer remarkably improves energy efficiency across a wide spectrum of broadcast protocols and that the total number of packet transmissions can be reduced consistently by 47% on average. In the study of the impact of link correlation model on diversity-based protocols, we propose link correlation aware network coding and link correlation aware opportunistic routing. In link correlation aware network coding, we introduce Correlated Coding which seeks to optimize the transmission efficiency by maximizing necessary coding opportunities. In link correlation aware opportunistic routing, we propose a novel candidate forwarder selection algorithm to help opportunistic routing fully exploit the diversity benefit of the wireless broadcast medium. Testbed evaluation and extensive simulation show that the traditional network coding and opportunistic routing protocols’ transmission efficiency is significantly improved with our link correlation model