Analysis Of Electronic Voting Schemes In The Real World

Voting is at the heart of a country’s democracy. Assurance in the integrity of the electoral process is pivotal for voters to have any trust in the system. Often, electronic voting schemes proposed in the literature, or even implemented in real world elections do not always consider all issues that may exist in the environment in which they might be deployed. In this paper, we identify some real - world issues and threats to electronic voting schemes. We then use the threats we have identified to present an analysis of schemes recently used in Australia and Estonia and present recommendations to mitigate threats to such schemes when deployed in an untrustworthy environment

Analysis and Design of Authentication and Encryption Algorithms for Secure Cloud Systems

Along with the fast growth of networks and mobile devices, cloud computing has become one of the most attractive and effective technologies and business solutions nowadays. Increasing numbers of organizations and customers are migrating their businesses and data to the cloud due to the flexibility and cost-efficiency of cloud systems. Preventing unauthorized access of sensitive data in the cloud has been one of the biggest challenges when designing a secure cloud system, and it strongly relies on the chosen authentication and encryption algorithms for providing authenticity and confidentiality, respectively. This thesis investigates various aspects of authentication and encryption algorithms for securing cloud systems, including authenticated encryption modes of operation, block ciphers, password hashing algorithms, and password-less/two-factor authentication mechanisms. Improving Authenticated Encryption Modes. The Galois/Counter Mode (GCM) is an authenticated encryption mode of operation for block ciphers. It has been widely adopted by many network standards and protocols that protect the security of cloud communications, such as TLS v1.2, IEEE 802.1AE and IPsec. Iwata et al. recently found a flaw in GCM's original proofs for non-96-bit nonce cases, and then presented new security bounds for GCM. The new bounds imply that the success probabilities of adversaries for attacking GCM are much larger than the originally expected ones. We propose a simple change to repair GCM. When applied, it will improve the security bounds by a factor of about $2^{20}$ while maintaining most of the original proofs. Analyzing Polynomial-Based Message Authentication Codes. We investigate attacks on polynomial-based message authentication code (MAC) schemes including the one adopted in GCM. We demonstrate that constructing successful forgeries of these MAC schemes does not necessarily require hash collisions. This discovery removes certain restrictions in the attacks previously proposed by Procter and Cid. Moreover, utilizing a special design of GCM for processing non-96-bit nonces, we turn these forgery attacks into birthday attacks, which will significantly increase their success probabilities. Therefore, by considering the birthday attacks and the security proof flaw found by Iwata et al., cloud system designers should avoid using GCM with non-96-bit nonces if they do not revise the design of GCM. Analyzing Block Ciphers. We propose a new framework for analyzing symmetric-key ciphers by guessing intermediate states to divide ciphers into small components. This framework is suitable for lightweight ciphers with simple key schedules and block sizes smaller than key lengths. Using this framework, we design new attacks on the block cipher family KATAN. These attacks can recover the master keys of 175-round KATAN32, 130-round KATAN48 and 112-round KATAN64 faster than exhaustive search, and thus reach many more rounds than the existing attacks. We also provide new attacks on 115-round KATAN32 and 100-round KATAN48 in order to demonstrate that this new kind of attack can be more time-efficient and memory-efficient than the existing ones. Designing Password Hashing Algorithms. Securely storing passwords and deriving cryptographic keys from passwords are also crucial for most secure cloud system designs. However, choices of well-studied password hashing algorithms are extremely limited, as their security requirements and design principles are different from common cryptographic primitives. We propose two practical password hashing algorithms, Pleco and Plectron. They are built upon well-understood cryptographic algorithms, and combine the advantages of symmetric-key and asymmetric-key primitives. By employing the Rabin cryptosystem, we prove that the one-wayness of Pleco is at least as strong as the hard problem of integer factorization. In addition, both password hashing algorithms are designed to be sequential memory-hard, in order to thwart large-scale password searching using parallel hardware, such as GPUs, FPGAs, and ASICs. Designing Password-less/Two-Factor Authentication Mechanisms. Motivated by a number of recent industry initiatives, we propose Loxin, an innovative solution for password-less authentication for cloud systems and web applications. Loxin aims to improve on passwords with respect to both usability and security. It utilizes push message services for mobile devices to initiate authentication transactions based on asymmetric-key cryptography, and enables users to access multiple services by using pre-owned identities, such as email addresses. In particular, the Loxin server cannot generate users' authentication credentials, thereby eliminating the potential risk of credential leakage if the Loxin server gets compromised. Furthermore, Loxin is fully compatible with existing password-based authentication systems, and thus can serve as a two-factor authentication mechanism

We the People, Constitutional Accountability, and Outsourcing Government

The ubiquitous outsourcing of federal functions to private contractors, although benign in the main, raises the most fundamental of constitutional questions: What institutions and actors comprise the “federal government” itself? From Abu Ghraib to Blackwater, a string of scandals has heightened public awareness that highly sensitive federal powers and responsibilities are routinely entrusted to government contractors. At the same time, the American populace seems vaguely aware that, when it comes to ensuring accountability for errors and abuses of power, contractors occupy a special space. The fact is that myriad structural and procedural means for holding traditionally government actors accountable do not apply to private contractors exercising identical powers. This accountability vacuum is not remedied by prevailing constitutional doctrine, which ignores the realities of modern government by drawing an artificial line between the public and private spheres. I have thus argued previously that all private contractors should be viewed as anatomically related to other quasi-government entities such as independent agencies, residing along a single continuum of constitutional accountability. This Article builds on that premise by positing that private-public relationships be structured to ensure accountability as a matter of constitutional law

We the People, Constitutional Accountability, and Outsourcing Government

The ubiquitous outsourcing of federal functions to private contractors, although benign in the main, raises the most fundamental of constitutional questions: What institutions and actors comprise the federal government itself? From Abu Ghraib to Blackwater, a string of scandals has heightened public awareness that highly sensitive federal powers and responsibilities are routinely entrusted to government contractors. At the same time, the American populace seems vaguely aware that, when it comes to ensuring accountability for errors and abuses of power, contractors occupy a special space. The fact is that myriad structural and procedural means for holding traditionally government actors accountable do not apply to private contractors exercising identical powers. This accountability vacuum is not remedied by prevailing constitutional doctrine, which ignores the realities of modern government by drawing an artificial line between the public and private spheres. I have thus argued previously that all private contractors should be viewed as anatomically related to other quasi-government entities such as independent agencies, residing along a single continuum of constitutional accountability. This Article builds on that premise by positing that private-public relationships be structured to ensure accountability as a matter of constitutional law

Vulnerability assessment of modern ICT infrastructure from an information warfare perspective.

Ph. D. University of KwaZulu-Natal, Durban 2011.The overall objective of the study is to provide a vulnerability assessment of the mobile communications infrastructure to information warfare attacks; this study has a South African focus. The mobile infrastructure was selected as the infrastructure and mobile devices incorporate the majority of modern ICT technologies, namely social networking, wireless connectivity and mobility, mass storage, as well as the telecommunications elements. The objectives of the study are to: Propose a new information warfare model, and from this deduce a vulnerability assessment framework from the specific information warfare perspective. These are the guiding frameworks and model for the study. Gather information regarding threats and vulnerabilities, with particular focus on potential use in information warfare and relevance to South Africa. Establish the criticality of the mobile infrastructure in South Africa. Use the gathered information in the vulnerability assessment, to assess the vulnerability of the mobile infrastructure and related devices and services. The model and framework are generated through desk-based research. The information is gathered from research protocols that are relevant to both research and risk and vulnerability assessment, these include: expert input through interviews and a research workshop, incident and trend analyses through news and vendor reports and academic publishing, computer simulation, questionnaire survey, and mathematical analyses. The information is then triangulated by using it in the vulnerability assessment. The primary and secondary data shows that attacks on confidentiality are the most prevalent for both computer-based networks and the mobile infrastructure. An increase in threats and incidents for both computer and mobile platforms is being seen. The information security trends in South Africa indicate that the existing security concerns are likely to worsen, in particular the high infection rates. The research indicates that the mobile infrastructure is critical in South Africa. The study validates the proposed framework, which indicates that South Africa is vulnerable to an information warfare attack in general. Key aspects of vulnerability in the mobile infrastructure are highlighted; the apparent high load of the mobile infrastructure in South Africa can be seen as a high risk vulnerability. Suggestions to mitigate vulnerabilities and threats are provided