Results 1  10
of
142
Atomic Broadcast: From Simple Message Diffusion to Byzantine Agreement
 Information and Computation
, 1985
"... In distributed systems subject to random communication delays and component failures, atomic broadcast can be used to implement the abstraction of synchronous replicated storage, a distributed storage that displays the same contents at every correct processor as of any clock time. This paper present ..."
Abstract

Cited by 217 (15 self)
 Add to MetaCart
In distributed systems subject to random communication delays and component failures, atomic broadcast can be used to implement the abstraction of synchronous replicated storage, a distributed storage that displays the same contents at every correct processor as of any clock time. This paper presents a systematic derivation of a family of atomic broadcast protocols that are tolerant of increasingly general failure classes: omission failures, timing failures, and authenticationdetectable Byzantine failures. The protocols work for arbitrary pointtopoint network topologies, and can tolerate any number of link and process failures up to network partitioning. After proving their correctness, we also prove two lower bounds that show that the protocols provide in many cases the best possible termination times. Keywords and phrases: Atomic Broadcast, Byzantine Agreement, Computer Network, Correctnesss, Distributed System, Failure Classification, FaultTolerance, Lower Bound, RealTime Syste...
Shortestpath and minimumdelay algorithms in networks with timedependent edgelength
 Journal of the ACM
, 1990
"... We consider in this paper the shortestpath problem in networks in which the delay (or weight) of the edges changes with time according to arbitrary functions. We present algorithms for finding the shortestpath and minimumdelay under various waiting constraints and investigate the properties of th ..."
Abstract

Cited by 95 (6 self)
 Add to MetaCart
We consider in this paper the shortestpath problem in networks in which the delay (or weight) of the edges changes with time according to arbitrary functions. We present algorithms for finding the shortestpath and minimumdelay under various waiting constraints and investigate the properties of the derived path. We show that if departure time from the source node is unrestricted then a shortest path can be found that is simple and achieves a delay as short as the most unrestricted path. In the case of restricted transit, it is shown that there exist cases where the minimum delay is finite but the path that achieves it is infinite.
StateOptimal SnapStabilizing PIF in Tree Networks (Extended Abstract)
 In Proceedings of the Fourth Workshop on SelfStabilizing Systems
, 1999
"... ) Alain Bui, 1 Ajoy K. Datta, 2 Franck Petit, 1 Vincent Villain 1 1 LaRIA, Universit e de Picardie Jules Verne, France 2 Department of Computer Science, University of Nevada, Las Vegas Abstract In this paper, we introduce the notion of snapstabilization. A snapstabilizing algorithm proto ..."
Abstract

Cited by 50 (25 self)
 Add to MetaCart
) Alain Bui, 1 Ajoy K. Datta, 2 Franck Petit, 1 Vincent Villain 1 1 LaRIA, Universit e de Picardie Jules Verne, France 2 Department of Computer Science, University of Nevada, Las Vegas Abstract In this paper, we introduce the notion of snapstabilization. A snapstabilizing algorithm protocol guarantees that, starting from an arbitrary system configuration, the protocol always behaves according to its specification. So, a snapstabilizing protocol is a selfstabilizing protocol which stabilizes in 0 steps. We propose a snapstabilizing Propagation of Information with Feedback (PIF) scheme on a rooted tree network. We call this scheme Propagation of information with Feedback and Cleaning (PFC). We present two algorithms. The first one is a basic PFC scheme which is inherently snapstabilizing. However, it can be delayed O(h 2 ) steps (where h is the height of the tree) due to some undesirable local states. The second algorithm improves the worst delay of the basic PFC algori...
LoopFree Multipath Routing Using Generalized Diffusing Computations
, 1998
"... A new distributed algorithm for the dynamic computation of multiple loopfree paths from source to destination in a computer network or internet are presented, validated, and analyzed. According to this algorithms, which is called DASM (Diffusing Algorithm for Shortest Multipath), each router maint ..."
Abstract

Cited by 47 (4 self)
 Add to MetaCart
A new distributed algorithm for the dynamic computation of multiple loopfree paths from source to destination in a computer network or internet are presented, validated, and analyzed. According to this algorithms, which is called DASM (Diffusing Algorithm for Shortest Multipath), each router maintains a set of entries for each destination in its routing table, and each such entry consists of a set of tuples specifying the next router and distance in a loopfree path to the destination. DASM guarantees instantaneous loop freedom of multipath routing tables by means of a generalization of Dijkstra and Scholten's diffusing computations. With generalized diffusing computations, a node in a directed acyclic graph (DAG) defined for a given destination has multiple next nodes in the DAG and is able to modify the DAG without creating a directed loop. DASM is shown to be loopfree at every instant, and its average performance is analyzed by simulation and compared against an ideal linkstate ...
Selfstabilization by Counter Flushing
 IN PODC94 PROCEEDINGS OF THE THIRTEENTH ANNUAL ACM SYMPOSIUM ON PRINCIPLES OF DISTRIBUTED COMPUTING
, 1994
"... A useful way to design simple and robust protocols is to make them selfstabilizing. A protocol ..."
Abstract

Cited by 39 (5 self)
 Add to MetaCart
A useful way to design simple and robust protocols is to make them selfstabilizing. A protocol
A modular technique for the design of efficient distributed leader finding algorithms
 ACM Transactions on Programming Languages and Systems
, 1990
"... A general, modular technique for designing efficient leader finding algorithms in distributed, asynchronous networks is developed. This technique reduces the relatively complex problem of efficient leader finding to a simpler problem of efficient serial traversing of the corresponding network. The m ..."
Abstract

Cited by 36 (8 self)
 Add to MetaCart
A general, modular technique for designing efficient leader finding algorithms in distributed, asynchronous networks is developed. This technique reduces the relatively complex problem of efficient leader finding to a simpler problem of efficient serial traversing of the corresponding network. The message complexity of the resulting leader finding algorithms is bounded by ( f (n) + n)(log2k + 1) [or ( f (m) + n)(log2k + 1)], where n is the number of nodes in the network [m is the number of edges in the network], k is the number of nodes that start the algorithm, and f (n) [f (m)] is the message complexity of traversing the nodes [edges] of the network. This technique does not require that the FIFO discipline is obeyed by the links. The local memory needed for each node, besides the memory needed for the traversal algorithm, is logarithmic in the maximal identity of a node in the network. This result achieves in a unified way the best known upper bounds on the message complexity of leader finding algorithms for circular, complete and general networks. It is also shown to be applicable to other classes of networks, and in some cases the message complexity of the resulted algorithms is better by a constant factor than that of previously known algorithms.
Decentralized Intrusion Detection in Wireless Sensor Networks
 PROCEEDINGS OF THE 1ST ACM INTERNATIONAL WORKSHOP ON QUALITY OF SERVICE & SECURITY IN WIRELESS AND MOBILE NETWORKS (Q2SWINET'05)
, 2005
"... Wireless sensor networks (WSNs) have many potential applications. Furthermore, in many scenarios WSNs are of interest to adversaries and they become susceptible to some types of attacks since they are deployed in open and unprotected environments and are constituted of cheap small devices. Preventiv ..."
Abstract

Cited by 33 (0 self)
 Add to MetaCart
Wireless sensor networks (WSNs) have many potential applications. Furthermore, in many scenarios WSNs are of interest to adversaries and they become susceptible to some types of attacks since they are deployed in open and unprotected environments and are constituted of cheap small devices. Preventive mechanisms can be applied to protect WSNs against some types of attacks. However, there are some attacks for which there is no known prevention methods. For these cases, it is necessary to use some mechanism of intrusion detection. Besides preventing the intruder from causing damages to the network, the intrusion detection system (IDS) can acquire information related to the attack techniques, helping in the development of prevention systems. In this work we propose an IDS that fits the demands and restrictions of WSNs. Simulation results reveal that the proposed IDS is efficient and accurate in detecting different kinds of simulated attacks.
Distributed algorithms for Unidirectional networks
 SIAM J. Comput
, 1993
"... We address the question of distributively computing over a strongly connected unidirectional data communication network. In unidirectional networks the existence of a communication link from one node to another does not imply the existence of a link in the opposite direction. The strong connectiv ..."
Abstract

Cited by 31 (3 self)
 Add to MetaCart
We address the question of distributively computing over a strongly connected unidirectional data communication network. In unidirectional networks the existence of a communication link from one node to another does not imply the existence of a link in the opposite direction. The strong connectivity means that from every node there is a directed path to any other node. We assume an arbitrary topology network in which the strong connectivity is the only restriction. Four models are considered: Synchronous and asynchronous, and for each we consider node space availability which grows as either O(1) bits or O(log n) bits per incident link, where n is the total number of nodes in the network. First we provide algorithms for two basic problems in distributed computing in data communication networks, traversal, and election. Each of these basic protocols produces two directed spanning trees rooted at a distinguished node in the network, one called intree, leading to the root, an...