Continuous After-the-fact Leakage-Resilient Key Exchange (full version)

Security models for two-party authenticated key exchange (AKE) protocols have developed over time to provide security even when the adversary learns certain secret keys. In this work, we advance the modelling of AKE protocols by considering more granular, continuous leakage of long-term secrets of protocol participants: the adversary can adaptively request arbitrary leakage of long-term secrets even after the test session is activated, with limits on the amount of leakage per query but no bounds on the total leakage. We present a security model supporting continuous leakage even when the adversary learns certain ephemeral secrets or session keys, and give a generic construction of a two-pass leakage-resilient key exchange protocol that is secure in the model; our protocol achieves continuous, after-the-fact leakage resilience with not much more cost than a previous protocol with only bounded, non-after-the-fact leakage

Bringing the OpenMI to LIFE Progress Report No. 4 - 31st March 2008 – 30th September 2008

The Water Framework Directive demands an integrated approach to water management. This requires the ability to predict how catchment processes will behave and interact in response to the activities of water managers and others. In most contexts, it is not feasible to build a single predictive model that adequately represents all the processes; therefore a means of linking models of individual processes is required. This is met by the FP5 HarmonIT project’s Open Modelling Interface and Environment (the OpenMI). The purpose of this project is to transform the OpenMI from a research output to a sustainable operational Standard. It will build the capacity to use the OpenMI and will demonstrate it under operational conditions. It will also develop, test and demonstrate the future support organisation for the OpenMI. Finally, information about the OpenMI will be disseminated to users

The impact of the proposed Emissions Trading Scheme on New Zealand’s economy

cap and trade, domestic policy, New Zealand, emissions trading scheme

Rethinking equilibrium conditions in macromonetary theory: A conceptually rigorous approach

Although still very much a minority view, there is a growing sense of unease about the high degree of abstraction involved in contemporary macro-monetary theory, in particular concerning its representative-agent microfoundation (see e.g. Colander et al., 2008; Goodhart, 2005, 2008; Buiter, 2009; Caballero, 2010; Hoover, 2010; Du Plessis, 2010; Meeusen, 2010). The paper shares this unease but questions another aspect of contemporary theory: its equilibrium conditions as consisting of its market coordination conditions and budget equation. The paper derives, from scratch, an alternative set of such conditions which it rigorously grounds in the nature of monetary exchange. This alternative set has implications for a wide variety of issues, including the aptness of MIU and CIA modelling, the nature of real and monetary disturbances, and the linkage between the financial and real sectors. The paper also assesses the conceptual soundness of commonly used constructs like Keynes’s income-spending (saving-investment) equation of IS analysis, Hicks’s wealth constraint, Fisher’s quantity equation, Walras’s Law, and the budget constraint of contemporary DSGE modelling.monetary exchange, equilibrium condition, budget equation, market coordination, market price

On the optimality of individual entangling-probe attacks against BB84 quantum key distribution

It is shown that an existing method to study ideal individual attacks on the BB84 QKD protocol using error discard can be adapted to reconciliation with error correction, and that an optimal attack can be explicitly found. Moreover, this attack fills Luetkenhaus bound, independently of whether error positions are leaked to Eve, proving that it is tight. In addition, we clarify why the existence of such optimal attacks is not in contradiction with the established ``old-style'' theory of BB84 individual attacks, as incorrectly suggested recently in a news feature.Comment: 12 pages, 3 figure

Quantifying Eulerian Eddy Leakiness in an Idealized Model

An idealized eddy‐resolving ocean basin, closely resembling the North Pacific Ocean, is simulated using MITgcm. We identify rotationally coherent Lagrangian vortices (RCLVs) and sea surface height (SSH) eddies based on the Lagrangian and Eulerian framework, respectively. General statistical results show that RCLVs have a much smaller coherent core than SSH eddies with the ratio of radius is about 0.5. RCLVs are often enclosed by SSH anomaly contours, but SSH eddy identification method fails to detect more than half of RCLVs. Based on their locations, two types of eddies are classified into three categories: overlapping RCLVs and SSH eddies, nonoverlapping SSH eddies, and nonoverlapping RCLVs. Using Lagrangian particles, we examine the processes of leakage and intrusion around SSH eddies. For overlapping SSH eddies, over the lifetime, the material coherent core only accounts for about 25% and about 50% of initial water leak from eddy interior. The remaining 25% of water can still remain inside the boundary, but only in the form of filaments outside the coherent core. For nonoverlapping SSH eddies, more water leakage (about 60%) occurs at a faster rate. Guided by the number and radius of SSH eddies, fixed circles and moving circles are randomly selected to diagnose the material flux around these circles. We find that the leakage and intrusion trends of moving circles are quite similar to that of nonoverlapping SSH eddies, suggesting that the material coherence properties of nonoverlapping SSH eddies are not significantly different from random pieces of ocean with the same size