Lucia Draque Penso

Learn More
We investigate computational models with stabilizing properties. Such models include e.g. the partially synchronous model [Dwork et al. 1988], where after some unknown global stabilization time the system complies to bounds on computing speeds and message delays, or the asynchronous model augmented with unreliable failure detectors [Chan-dra et al. 1996],(More)
We consider a connected undirected graph G(n, m) with n nodes and m edges. A k-dominating set D in G is a set of nodes having the property that every node in G is at most k edges away from at least one node in D. Finding a k-dominating set of minimum size is NP-hard. We give a new synchronous distributed algorithm to find a k-dominating set in G of size no(More)
In the k-set agreement problem [1], each process in a group starts with a private input value, communicates with the others, and then halts after choosing a private output value. Each process is required to choose some process's input, and at most k distinct values may be chosen. We consider this problem in an asynchronous message-passing system of n + 1(More)
We study the problem of Secure Multi-party Computation (SMC) in a model where individual processes contain a tamper-proof security module, and introduce the TrustedPals framework, an efficient smart card based implementation of SMC for any number of participating entities in such a model. Security modules can be trusted by other processes and can establish(More)
We investigate the problem of detecting termination of a distributed computation in systems where processes can fail by crashing. Specifically, when the communication topology is fully connected, we describe a way to transform any termination detection algorithm A that has been designed for a failure-free environment into a termination detection algorithm B(More)
This paper studies the impact of omission failures on asyn-chronous distributed systems with crash-stop failures. We provide two different transformations for algorithms, failure detectors, and problem specifications, one of which is weakest failure detector preserving. We prove that our transformation of failure detector Ω [1] is the weakest failure(More)
We investigate the problem of detecting termination of a distributed computation in systems where processes can fail by crashing. Specifically, when the communication topology is fully connected, we describe a way to transform any termination detection algorithm A that has been designed for a failure-free environment into a termination detection algorithm B(More)
This paper presents a modular redesign of TrustedPals, a smartcard-based security framework for solving secure multiparty computation (SMC). TrustedPals allows to reduce SMC to the problem of fault-tolerant consensus between smartcards. Within the redesign we investigate the problem of solving consensus in a general omission failure model augmented with(More)