Energy and Load Aware Multipath Route Selection for Mobile Ad hoc Networks

Routing protocols are crucial in delivering packets from source to destination in scenarios where destinations are not directly within the sender’s range. Various routing protocols employ different strategies, but their presence is indispensable for seamless data transfer from source to destination. Multipath routing, while offering load balancing, often falls short in efficiently distributing the network’s load, thus adversely impacting the vital communication resource—energy—due to packet loss. This paper introduces an Energy-Efficient Load-Aware Routing (ELAM) scheme to enhance the routing performance of Mobile Ad hoc Networks (MANETs). Our motivation stems from the observation that many multipath routing protocols are designed based on a single criterion, such as the shortest path, often neglecting load balancing or energy conservation. While the Ad Hoc On-Demand Multipath Distance Vector (AOMDV) protocol demonstrates improved performance compared to unipath routing schemes, achieving both load balancing and energy efficiency remains challenging.  The proposed ELAM scheme considers energy conservation, the shortest path, and load balancing to enhance the performance of multipath routing protocols. ELAM considers the shortest path and energy conservation while accommodating more than two paths in a MANET. We introduce an energy factor that contributes to the network’s lifespan, with efficient load balancing enhancing the longevity of nodes and the overall network. The energy factor provides insights into the energy status, and we evaluate the performance of AODV, AOMDV, and the proposed ELAM. The results demonstrate that the proposed scheme outperforms existing protocols and effectively manages unnecessary energy consumption by mobile nodes. Our performance analysis reveals a minimum 5% improvement in throughput and Packet Delivery Ratio (PDR), indicating reduced packet dropping and network delays

Australia’s energy options: renewables and efficiency

The world is wrestling with the challenge of ensuring an ongoing supply of energy that does not damage the environment while enabling billions of people to appreciate the benefits of modern life. Global interest in renewable technologies is accelerating the maturity of many of these energy sources. These efforts are vital if the quality of human life is to be improved across the planet without causing its further degradation. Energy underpins all aspects of modern life and generates many externalities that affect both the environment and society more broadly, such as the environmental consequences of extracting the raw materials used in all energy generation. All forms of energy generation create externalities, although not all have an influence on the climate. Numerous policies have been established to adjust for climatic externalities in the energy generation and to incentivise low carbon emission sources of energy. There is a complex interplay between technological and economic factors influencing the deployment of renewable technologies, the relative cost of generating energy from different sources, and the broader political and economic cycles. Given how fundamental reliable energy is for modern life the costs involved in mitigating climate change are substantial. The scale of change requires examining public policy outcomes throughout the world to ensure that interventions are producing effective results in Australia.   Related identifier: ISBN 0 85801 280

Regulatory Instruments for Deployment of Clean Energy Technologies

Answering to the formidable challenge of climate change calls for a quick transition to a future economy with a drastic reduction in GHG emissions. And this in turn requires the development and massive deployment of new low-carbon energy technologies as soon as possible. Although many of these technologies have been identified, the critical issue is how to make them happen at the global level, possibly by integrating this effort into a global climate regime. This paper discusses the preferred approaches to foster low-carbon energy technologies from a regulatory point of view. Specific promotion policies for energy efficiency and conservation, renewable energy, carbon capture and sequestration, and nuclear power are examined, but the focus is on the regulatory instruments that will be needed for the deployment of enhancements to electricity grids and the associated control systems so that they are able to integrate intelligent demand response, distributed generation and storage in an efficient, reliable & environmentally responsible manner. The paper also comments on the interactions between technology and climate change policies and provides recommendations for policy makers.Massachusetts Institute of Technology. Center for Energy and Environmental Policy Research

A cyber-enabled mission-critical system for post-flood response:Exploiting TV white space as network backhaul links

A crucial problem in post-flood recovery actions is the ability to rapidly establish communication and collaboration among rescuers to conduct timely and effective search and rescue (SAR) mission given disrupted telecommunication infrastructure to support the service. Aimed at providing such proximity service (ProSe) for mission-critical data exchange in the post-flood environment, the majority of existing solutions rely heavily upon ad-hoc networking approaches, which suffer from restricted communication range and the limited scope of interaction. As an effort to broaden the ProSe coverage and expand integrated global-local information exchange in the post-flood SAR activities, this paper proposes a novel network architecture in the form of a cyber-enabled mission-critical system (CEMCS) for acquiring and communicating post-flood emergency data by exploiting TV white space spectrum as network backhaul links. The primary method of developing the proposed system builds upon a layered architecture of wireless local, regional and wide-area communications, and incorporates collaborative network components among these layers. The desirable functionalities of CEMCS are showcased through formulation and the development of an efficient global search strategy exploiting a wide range of collaboration among network agents. The simulation results demonstrate the capability of CEMCS to provide ProSe in the post-flood scenarios as reflected by reliable network performance (e.g., packet delivery ratio nearing 80%-90%) and the optimality of efficient search algorithm

The Influence of Communication Range on Connectivity for Resilient Wireless Sensor Networks Using a Probabilistic Approach.

Wireless sensor networks (WSNs) consist of thousands of nodes that need to communicate with each other. However, it is possible that some nodes are isolated from other nodes due to limited communication range. This paper focuses on the influence of communication range on the probability that all nodes are connected under two conditions, respectively: (1) all nodes have the same communication range, and (2) communication range of each node is a random variable. In the former case, this work proves that, for 0menor queepsmenor quee^(-1) , if the probability of the network being connected is 0.36eps , by means of increasing communication range by constant C(eps) , the probability of network being connected is at least 1-eps. Explicit function C(eps) is given. It turns out that, once the network is connected, it also makes the WSNs resilient against nodes failure. In the latter case, this paper proposes that the network connection probability is modeled as Cox process. The change of network connection probability with respect to distribution parameters and resilience performance is presented. Finally, a method to decide the distribution parameters of node communication range in order to satisfy a given network connection probability is developed

A Cognitive TV White Space Access Framework

Given the current boom in applications and services for mobile devices, data traffic is rapidly expanding, with the consequence that increasing spectrum capacity is being mandated. Following the switchover from analogue to digital platforms, Television White Space (TVWS) affords a fertile opportunity to supplement existing licensed spectrum to ease this scarcity. There are however, a number of obstacles to wide-scale TVWS adoption, including the accurate detection of primary users (PU), the hidden node problem and bandwidth availability for unlicensed secondary users (SU). Regulatory and industry bodies have sought to address some of these issues using a static database for spectrum access decisions, though this involves manual maintenance and accuracy can be compromised due to a lack of real-time information. While the new IEEE802.11af wireless local area network (WLAN) standard attempts to resolve some SU access issues, there remain many challenges, such as the critical asymmetry between mobile and base station power resources. This thesis presents a new cognitive TVWS access framework encompassing a real-time sensing paradigm for TVWS deployment that uses a spectrum-efficient scheme to uphold quality-of-service (QoS) for both PU and SU. A novel dynamic spectrum allocation (DSA) model has been formulated allied with a resilient interference management system which exploits the unique way digital terrestrial TV channels are allocated in different geographical areas. A margin strategy has been framed to support efficient TVWS channel reuse, with an exclusion zone established to overcome the hidden node problem, while an innovative routing algorithm using cross-layer information, both extends coverage capacity and maximises QoS provision by ensuring a more balanced resource allocation. Critical evaluation of the new access framework confirms that significant QoS improvements for SU are achieved compared to existing TVWS techniques. It importantly embodies a generic, practical, resource-efficient solution for TVWS deployment, which is compliant with current PU regulatory requirements

Enforcement and Spectrum Sharing: Case Studies of Federal-Commercial Sharing

To promote economic growth and unleash the potential of wireless broadband, there is a need to introduce more spectrally efficient technologies and spectrum management regimes. That led to an environment where commercial wireless broadband need to share spectrum with the federal and non-federal operations. Implementing sharing regimes on a non-opportunistic basis means that sharing agreements must be implemented. To have meaning, those agreements must be enforceable.\ud \ud With the significant exception of license-free wireless systems, commercial wireless services are based on exclusive use. With the policy change facilitating spectrum sharing, it becomes necessary to consider how sharing might take place in practice. Beyond the technical aspects of sharing, that must be resolved lie questions about how usage rights are appropriately determined and enforced. This paper is reasoning about enforcement in a particular spectrum bands (1695-1710 MHz and 3.5 GHz) that are currently being proposed for sharing between commercial services and incumbent spectrum users in the US. We examine three enforcement approaches, exclusion zones, protection zones and pure ex post and consider their implications in terms of cost elements, opportunity cost, and their adaptability

An Assessment of PIER Electric Grid Research 2003-2014 White Paper

This white paper describes the circumstances in California around the turn of the 21st century that led the California Energy Commission (CEC) to direct additional Public Interest Energy Research funds to address critical electric grid issues, especially those arising from integrating high penetrations of variable renewable generation with the electric grid. It contains an assessment of the beneficial science and technology advances of the resultant portfolio of electric grid research projects administered under the direction of the CEC by a competitively selected contractor, the University of California’s California Institute for Energy and the Environment, from 2003-2014