ANCHOR: logically-centralized security for Software-Defined Networks

While the centralization of SDN brought advantages such as a faster pace of innovation, it also disrupted some of the natural defenses of traditional architectures against different threats. The literature on SDN has mostly been concerned with the functional side, despite some specific works concerning non-functional properties like 'security' or 'dependability'. Though addressing the latter in an ad-hoc, piecemeal way, may work, it will most likely lead to efficiency and effectiveness problems. We claim that the enforcement of non-functional properties as a pillar of SDN robustness calls for a systemic approach. As a general concept, we propose ANCHOR, a subsystem architecture that promotes the logical centralization of non-functional properties. To show the effectiveness of the concept, we focus on 'security' in this paper: we identify the current security gaps in SDNs and we populate the architecture middleware with the appropriate security mechanisms, in a global and consistent manner. Essential security mechanisms provided by anchor include reliable entropy and resilient pseudo-random generators, and protocols for secure registration and association of SDN devices. We claim and justify in the paper that centralizing such mechanisms is key for their effectiveness, by allowing us to: define and enforce global policies for those properties; reduce the complexity of controllers and forwarding devices; ensure higher levels of robustness for critical services; foster interoperability of the non-functional property enforcement mechanisms; and promote the security and resilience of the architecture itself. We discuss design and implementation aspects, and we prove and evaluate our algorithms and mechanisms, including the formalisation of the main protocols and the verification of their core security properties using the Tamarin prover.Comment: 42 pages, 4 figures, 3 tables, 5 algorithms, 139 reference

A survey on cyber security for smart grid communications

A smart grid is a new form of electricity network with high fidelity power-flow control, self-healing, and energy reliability and energy security using digital communications and control technology. To upgrade an existing power grid into a smart grid, it requires significant dependence on intelligent and secure communication infrastructures. It requires security frameworks for distributed communications, pervasive computing and sensing technologies in smart grid. However, as many of the communication technologies currently recommended to use by a smart grid is vulnerable in cyber security, it could lead to unreliable system operations, causing unnecessary expenditure, even consequential disaster to both utilities and consumers. In this paper, we summarize the cyber security requirements and the possible vulnerabilities in smart grid communications and survey the current solutions on cyber security for smart grid communications. © 2012 IEEE

Cloud Security : A Review of Recent Threats and Solution Models

The most significant barrier to the wide adoption of cloud services has been attributed to perceived cloud insecurity (Smitha, Anna and Dan, 2012). In an attempt to review this subject, this paper will explore some of the major security threats to the cloud and the security models employed in tackling them. Access control violations, message integrity violations, data leakages, inability to guarantee complete data deletion, code injection, malwares and lack of expertise in cloud technology rank the major threats. The European Union invested €3m in City University London to research into the certification of Cloud security services. This and more recent developments are significant in addressing increasing public concerns regarding the confidentiality, integrity and privacy of data held in cloud environments. Some of the current cloud security models adopted in addressing cloud security threats were – Encryption of all data at storage and during transmission. The Cisco IronPort S-Series web security appliance was among security solutions to solve cloud access control issues. 2-factor Authentication with RSA SecurID and close monitoring appeared to be the most popular solutions to authentication and access control issues in the cloud. Database Active Monitoring, File Active Monitoring, URL Filters and Data Loss Prevention were solutions for detecting and preventing unauthorised data migration into and within clouds. There is yet no guarantee for a complete deletion of data by cloud providers on client requests however; FADE may be a solution (Yang et al., 2012)

Deploying fog-to-cloud towards a security architecture for critical infrastructure scenarios

Critical infrastructures are bringing security, and safety for people in terms of healthcare, water, electricity, industry, transportation, etc. The huge amount of data produced by CIs need to be aggregated, filtered, and stored. Cloud computing was merged into the CIs for utilizing cloud data centers as a pay-as-you-go online computing system for outsourcing services for data storage, filtering and aggregating. On the other hand, CIs need real-time processing for providing sophisticated services to people. Consequently, fog computing is merged into CIs aimed at providing services closer to the users, turning into a smooth real-time decision making and processing. When considering both, that is fog and cloud (for example, deploying the recently coined hierarchical fog-to-cloud F2C concept), new enriched features may be applied to the CIs. Security in CIs is one of the most essential challenges since any failure or attack can turn into a national wise disaster. Moreover, CIs also need to support quality of service (QoS) guarantees for users. Thus, bringing balanced QoS vs security is one of the main challenges for any CI infrastructure. In this paper, we illustrate the benefits of deploying an F2C system in CIs, particularly identifying specific F2C security requirements to be applied to CIs. Finally, we also introduce a decoupled security architecture specifically tailored to CIs that can bring security with reasonable QoS in terms of authentication and key distribution time delay.This work has been supported by the Spanish Ministry of Science, Innovation and Universities and the European Regional Development Fund (FEDER) under contract RTI2018-094532-B-I00, and by the H2020 European Union mF2C project with reference 730929.Peer ReviewedPostprint (author's final draft

Towards ensuring scalability, interoperability and efficient access control in a multi-domain grid-based environment

The application of grid computing has been hampered by three basic challenges: scalability, interoperability and efficient access control which need to be optimized before a full-scale adoption of grid computing can take place. To address these challenges, a novel architectural model was designed for a multi-domain grid based environment (built on three domains). It was modelled using the dynamic role-based access control. The architecture’s framework assumes that each domain has an independent local security monitoring unit and a central security monitoring unit that monitors security for the entire grid. The architecture was evaluated using the Grid Security Services Simulator, a meta-query language and Java Runtime Environment 1.7.0.5 for implementing the workflows that define the model’s task. In terms of scalability, the results show that as the number of grid nodes increases, the average turnaround time reduces, and thereby increases the number of service requesters (grid users) on the grid. Grid middleware integration across various domains as well as the appropriate handling of authentication and authorisation through a local security monitoring unit and a central security monitoring unit proved that the architecture is interoperable. Finally, a case study scenario used for access control across the domains shows the efficiency of the role based access control approach used for achieving appropriate access to resources. Based on the results obtained, the proposed framework has proved to be interoperable, scalable and efficiently suitable for enforcing access control within the parameters evaluated.Department of HE and Training approved lis

Systematizing Decentralization and Privacy: Lessons from 15 Years of Research and Deployments

Decentralized systems are a subset of distributed systems where multiple authorities control different components and no authority is fully trusted by all. This implies that any component in a decentralized system is potentially adversarial. We revise fifteen years of research on decentralization and privacy, and provide an overview of key systems, as well as key insights for designers of future systems. We show that decentralized designs can enhance privacy, integrity, and availability but also require careful trade-offs in terms of system complexity, properties provided, and degree of decentralization. These trade-offs need to be understood and navigated by designers. We argue that a combination of insights from cryptography, distributed systems, and mechanism design, aligned with the development of adequate incentives, are necessary to build scalable and successful privacy-preserving decentralized systems