3 research outputs found
Self-stabilizing algorithms for Connected Vertex Cover and Clique decomposition problems
In many wireless networks, there is no fixed physical backbone nor
centralized network management. The nodes of such a network have to
self-organize in order to maintain a virtual backbone used to route messages.
Moreover, any node of the network can be a priori at the origin of a malicious
attack. Thus, in one hand the backbone must be fault-tolerant and in other hand
it can be useful to monitor all network communications to identify an attack as
soon as possible. We are interested in the minimum \emph{Connected Vertex
Cover} problem, a generalization of the classical minimum Vertex Cover problem,
which allows to obtain a connected backbone. Recently, Delbot et
al.~\cite{DelbotLP13} proposed a new centralized algorithm with a constant
approximation ratio of for this problem. In this paper, we propose a
distributed and self-stabilizing version of their algorithm with the same
approximation guarantee. To the best knowledge of the authors, it is the first
distributed and fault-tolerant algorithm for this problem. The approach
followed to solve the considered problem is based on the construction of a
connected minimal clique partition. Therefore, we also design the first
distributed self-stabilizing algorithm for this problem, which is of
independent interest
Snap-Stabilization in Message-Passing Systems
In this paper, we tackle the open problem of snap-stabilization in
message-passing systems. Snap-stabilization is a nice approach to design
protocols that withstand transient faults. Compared to the well-known
self-stabilizing approach, snap-stabilization guarantees that the effect of
faults is contained immediately after faults cease to occur. Our contribution
is twofold: we show that (1) snap-stabilization is impossible for a wide class
of problems if we consider networks with finite yet unbounded channel capacity;
(2) snap-stabilization becomes possible in the same setting if we assume
bounded-capacity channels. We propose three snap-stabilizing protocols working
in fully-connected networks. Our work opens exciting new research perspectives,
as it enables the snap-stabilizing paradigm to be implemented in actual
networks