title: Secure voting in the cloud using homomorphic encryption and mobile agents

authors: Will, Mark Antony

abstract: While governments are transitioning to the cloud to leverage efficiency, transparency and accessibility advantages, public opinion - the backbone of democracy - is being left behind. Statistics show that traditional paper voting is failing to reach the technological-savvy generation, with voter turnout decreasing every election for many first-world countries. Remote electronic voting is a possible solution facilitator to this problem, but it still faces several security, privacy and accountability concerns. This paper introduces a practical application of partially homomorphic encryption to help address these challenges. We describe a cloud-based mobile electronic voting scheme, evaluating its security against a list of requirements, and benchmarking performance on the cloud and mobile devices. In order to protect voter privacy, we propose moving away from a public bulletin board so that no individual cipher votes are saved, while still allowing vote verification. As the majority of the security threats faced by electronic voting are from the underlying system, we also introduce the novel concept of using a dedicated hardware server for homomorphic tallying and decryption.

text: Secure voting in the cloud using homomorphic encryption and mobile agents While governments are transitioning to the cloud to leverage efficiency, transparency and accessibility advantages, public opinion - the backbone of democracy - is being left behind. Statistics show that traditional paper voting is failing to reach the technological-savvy generation, with voter turnout decreasing every election for many first-world countries. Remote electronic voting is a possible solution facilitator to this problem, but it still faces several security, privacy and accountability concerns. This paper introduces a practical application of partially homomorphic encryption to help address these challenges. We describe a cloud-based mobile electronic voting scheme, evaluating its security against a list of requirements, and benchmarking performance on the cloud and mobile devices. In order to protect voter privacy, we propose moving away from a public bulletin board so that no individual cipher votes are saved, while still allowing vote verification. As the majority of the security threats faced by electronic voting are from the underlying system, we also introduce the novel concept of using a dedicated hardware server for homomorphic tallying and decryption.

year: 2015

title: Failure resilience and traffic engineering for multi-controller software defined networking

authors: Zaicu, Nicu Florin

abstract: This thesis explores and proposes solutions to address the challenges faced by Multi-Controller SDN (MCSDN) systems when deploying TE optimisation on WANs. Despite the interest from the research community, existing MCSDN systems present limitations. For example, TE optimisation systems are computationally complex, have high consistency requirements, and need network-wide state to operate. Because of such requirements, MCSDN systems can encounter performance overheads and state consistency problems when implementing TE. Moreover, performance and consistency problems are more prominent when deploying the system on WANs as these network types have higher inter-device latency, delaying state propagation.

Unlike existing literature, this thesis presents several design choices that address all four challenges affecting MCSDN systems (scalability, consistency, resilience, and coordination). We use the presented design choices to build Helix, a hierarchical MCSDN system. Helix provides better scalability, performance and failure resilience compared to existing MCSDN systems by sharing minimal state between controllers, offloading operations closer to the data plane and deploying lightweight tasks.

A challenge that we faced when building Helix was that existing TE algorithms did not meet Helix's design choices. This thesis presents a new CSPF-based TE algorithm that needs minimal state to operate and supports offloading inter-area TE to local controllers, fulfilling Helix's requirements. Helix's TE algorithm provides better performance and forwarding stability, addressing 1.6x more congestion while performing up to 29x fewer path modifications than the other algorithms evaluated in our experiments.

While MCSDN literature has explored evaluating different aspects of system performance, there is a lack of readily available tools and concrete testing methodologies. To this end, this thesis provides concrete testing methodologies and tools readily available to the MCSDN community to evaluate the data plane failure resilience, control plane failure resilience, and TE optimisation performance of MCSDN systems.

text: Failure resilience and traffic engineering for multi-controller software defined networking This thesis explores and proposes solutions to address the challenges faced by Multi-Controller SDN (MCSDN) systems when deploying TE optimisation on WANs. Despite the interest from the research community, existing MCSDN systems present limitations. For example, TE optimisation systems are computationally complex, have high consistency requirements, and need network-wide state to operate. Because of such requirements, MCSDN systems can encounter performance overheads and state consistency problems when implementing TE. Moreover, performance and consistency problems are more prominent when deploying the system on WANs as these network types have higher inter-device latency, delaying state propagation.

Unlike existing literature, this thesis presents several design choices that address all four challenges affecting MCSDN systems (scalability, consistency, resilience, and coordination). We use the presented design choices to build Helix, a hierarchical MCSDN system. Helix provides better scalability, performance and failure resilience compared to existing MCSDN systems by sharing minimal state between controllers, offloading operations closer to the data plane and deploying lightweight tasks.

A challenge that we faced when building Helix was that existing TE algorithms did not meet Helix's design choices. This thesis presents a new CSPF-based TE algorithm that needs minimal state to operate and supports offloading inter-area TE to local controllers, fulfilling Helix's requirements. Helix's TE algorithm provides better performance and forwarding stability, addressing 1.6x more congestion while performing up to 29x fewer path modifications than the other algorithms evaluated in our experiments.

While MCSDN literature has explored evaluating different aspects of system performance, there is a lack of readily available tools and concrete testing methodologies. To this end, this thesis provides concrete testing methodologies and tools readily available to the MCSDN community to evaluate the data plane failure resilience, control plane failure resilience, and TE optimisation performance of MCSDN systems.

year: 2022

title: The Māori Data Privacy Framework: How useful is it for hapū?

authors: Clark, Vanessa

abstract: This brief is a part of a series, produced for the Tikanga in Technology (TiNT) research programme, that provides a hapū perspective on data sovereignty, data governance, and data privacy. In this brief we focus on the Māori Data Privacy Framework developed by the TiNT team and assess how useful it is for hapū. To do so, we draw on a case study with Ngāti Tiipa, one of the 33 iwi and hapū of the Waikato confederation (Kukutai, Whitehead & Kani, 2022). This brief should be read in conjunction with TiNT Brief #2 Protecting hapū data privacy: A Ngāti Tiipa case study of technology considerations.

text: The Māori Data Privacy Framework: How useful is it for hapū? This brief is a part of a series, produced for the Tikanga in Technology (TiNT) research programme, that provides a hapū perspective on data sovereignty, data governance, and data privacy. In this brief we focus on the Māori Data Privacy Framework developed by the TiNT team and assess how useful it is for hapū. To do so, we draw on a case study with Ngāti Tiipa, one of the 33 iwi and hapū of the Waikato confederation (Kukutai, Whitehead & Kani, 2022). This brief should be read in conjunction with TiNT Brief #2 Protecting hapū data privacy: A Ngāti Tiipa case study of technology considerations.

year: 2025-02-11