Spectrum and transmission range aware clustering for cognitive radio ad hoc networks

Cognitive radio network (CRN) is a promising technology to overcome the problem of spectrum shortage by enabling the unlicensed users to access the underutilization spectrum bands in an opportunistic manner. On the other hand, the hardness of establishing a fixed infrastructure in specific situations such as disaster recovery, and battlefield communication imposes the network to have an ad hoc structure. Thus, the emerging of Cognitive Radio Ad Hoc Network (CRAHN) has accordingly become imperative. However, the practical implementation of CRAHN faced many challenges such as control channel establishment and the scalability problems. Clustering that divides the network into virtual groups is a reliable solution to handle these issues. However, previous clustering methods for CRAHNs seem to be impractical due to issues regarding the high number of constructed clusters and unfair load distribution among the clusters. Additionally, the homogeneous channel model was considered in the previous work despite channel heterogeneity is the CRN features. This thesis addressed these issues by proposing two clustering schemes, where the heterogeneous channel is considered in the clustering process. First, a distributed clustering algorithm called Spectrum and Transmission Range Aware Clustering (STRAC) which exploits the heterogeneous channel concept is proposed. Here, a novel cluster head selection function is formulated. An analytical model is derived to validate the STRAC outcomes. Second, in order to improve the bandwidth utilization, a Load Balanced Spectrum and Transmission Range Aware Clustering (LB-STRAC) is proposed. This algorithm jointly considers the channel heterogeneity and load balancing concepts. Simulation results show that on average, STRAC reduces the number of constructed clusters up to 51% compared to conventional clustering technique, Spectrum Opportunity based Clustering (SOC). In addition, STRAC significantly reduces the one-member cluster ratio and re-affiliation ratio in comparison to non-heterogeneity channel consideration schemes. LB-STRAC further improved the clustering performance by outperforming STRAC in terms of uniformity and equality of the traffic load distribution among all clusters with fair spectrum allocation. Moreover, LB-STRAC has been shown to be very effective in improving the bandwidth utilization. For equal traffic load scenario, LB-STRAC on average improves the bandwidth utilization by 24.3% compared to STRAC. Additionally, for varied traffic load scenario, LB-STRAC improves the bandwidth utilization by 31.9% and 25.4% on average compared with STRAC for non-uniform slot allocation and for uniform slot allocation respectively. Thus, LB-STRAC is highly recommended for multi-source scenarios such as continuous monitoring applications or situation awareness applications

Efficient Certificate Revocation of Attacker nodes in Mobile Ad Hoc Networks

Mobile Ad Hoc Networks (MANETs) is a self-configuring, infrastructure less network of mobile devices connected by wireless. The wireless and dynamic nature of MANET leads to various types of security attacks. The primary task is to provide the secure communication. To come across this challenge, we propose Cluster based Certificate Revocation with Vindication Capability scheme for certificate revocation from the attacker node and isolate the attackers from further communication in the network. In addition, we have adopted the one-hop neighbor selection method for none of the intermediate node is an attacker node from source to destination. This provides an effective and efficient secure communication in MANET

Occupation, colonialism, apartheid? A re-assessment of Israel’s practices in the occupied Palestinian territories under international law

This study was commissioned and coordinated by the Middle East Project (MEP) of the Democracy and Governance Programme, a research programme of the Human Sciences Research Council of South Africa. The genesis of this study was the suggestion made in January 2007 by Professor John Dugard, in his capacity as UN Special Rapporteur on the human rights situation in the occupied Palestinian territories, that Israel’s military occupation displays elements of colonialism and apartheid. The Human Sciences Research Council commissioned this study to scrutinise Professor Dugard’s hypothesis from the perspective of international law. Over a period of 15 months, the team of scholars engaged in extensive research, discussion, and rounds of lively debate through seven drafts. The result is the consensus represented in this report, offered here for public discussion. Constructive criticism is welcomed, in order that shortcomings in this document may be addressed in a future edition. Although this study is essentially a legal document, observations from other disciplines are encouraged

Developing an Ecological Social Justice Framework for Ocean Energy Technologies: Case Studies From the Phillipines

Unless subjected to skeptical and conscious scrutiny, environmentally-friendly ocean energy technologies can become Trojan machines of social inequity due to the subtle re-organizing influences of technologies on culture and the society. Environmental laws that promote or regulate ocean energy technologies can act as Trojan legal regimes in the absence of a framework for assessing and anticipating their adverse impacts on social justice. Environmental justice is inadequate for this task, so an alternative framework is proposed: ecological social justice, drawn from the Third Worlds perspective of sustainable development as equitable sharing. Though overshadowed by the prevalent notion of sustainable development as limits to growth, a review of international environmental law shows that the ideas of equitable sharing have persisted, underpinning demands for more equitable distribution of resources and environmental amenities, greater public participation in decision-making, and special attention in favor of specified social groups. Beginning with the critiques of environmental justice and then drawing upon a substantivist view of the role of the Economy as an ecological link between Society and Nature, a sketch of ecological social justice is drawn. The assessment of whether specific legal regimes or their implementation promote or hinder social justice revolve around three focal points: distribution, recognition, and participation, and pay special attention to the role of culture and power in society. The assessment also incorporates and emphasizes the local conception of social justice in order to remain true to its ecological character. To demonstrate, the paper conducts detailed case studies of the Philippines. The 1987 Constitution established a right to environment as a result of the historical evolution of a constitutional policy of promoting social justice, This caused Philippine environmental and ocean resource laws to incorporate provisions that promote ecological social justice. Analysis of Philippine ocean environment and energy laws and two internationally-recognized ocean energy projects reveals insights into how even the most environmentally-friendly but complex technologies can lead to domination and oppression, and how guiding ideals of equitable sharing at the local levels can lead to more socially-just solutions

Asian Yearbook of International Law, Volume 19 (2013)

The Yearbook aims to promote research, studies and writings in the field of international law in Asia, as well as to provide an intellectual platform for the discussion and dissemination of Asian views and practices on contemporary international legal issues. Readership: All interested in International Law and Asian Law

Macrocriminology and Freedom

How can power over others be transformed to 'power with'? It is possible to transform many institutions to build societies with less predation and more freedom. These stretch from families and institutions of gender to the United Nations. Some societies, times and places have crime rates a hundred times higher than others. Some police forces kill at a hundred times the rate of others. Some criminal corporations kill thousands more than others. Micro variables fail to explain these patterns. Prevention principles for that challenge are macrocriminological. Freedom is conceived in a republican way as non-domination. Tempering domination prevents crime; crime prevention reduces domination. Many believe a high crime rate is a price of freedom. Not Braithwaite. His principles of crime control are to build freedom, temper power, lift people from poverty and reduce all forms of domination. Freedom requires a more just normative order. It requires cascading of peace by social movements for non-violence and non-domination. Periods of war, domination and anomie cascade with long lags to elevated crime, violence, inter-generational self-violence and ecocide. Cybercrime today poses risks of anomic nuclear wars. Braithwaite’s proposals refine some of criminology’s central theories and sharpen their relevance to all varieties of freedom. They can be reduced to one sentence. Strengthen freedom to prevent crime, prevent crime to strengthen freedom