Baruch Awerbuch

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The problem of simulating a synchronous network by an asynchronous network is investigated. A new simulation technique, referred to as a synchronizer, which is a new, simple methodology for designing efficient distributed algorithms in asynchronous networks, is proposed. The synchronizer exhibits a trade-off between its communication and time complexities,(More)
Minimal delay routing is a fundamental task in networks. Since delays depend on the (potentially unpredictable) traffic distribution, online delay optimization can be quite challenging. While uncertainty about the current network delays may make the current routing choices sub-optimal, the algorithm can nevertheless try to learn the traffic patterns and(More)
In this paper, we analyze the behavior of communication networks in which packets are generated dynamically at the nodes and routed in discrete time steps across the edges. We focus on a basic adversarial model of packet generation and path determination for which the time–averaged injection rate of packets requiring the use of any edge is limited to be(More)
An ad hoc wireless network is an autonomous self-organizing system ofmobile nodes connected by wireless links where nodes not in directrange can communicate via intermediate nodes. A common technique usedin routing protocols for ad hoc wireless networks is to establish therouting paths on-demand, as opposed to continually maintaining acomplete routing(More)
This paper develops linear time distributed algorithms for a class of problems in an asynchronous communication network. Those problems include Minimum-Weight Spanning Tree (MST), Leader Election, counting the number of network nodes, and computing a sensitive decomposable function (e.g. majority, parity, maximum, OR, AND). The main problem considered is(More)
This abstract presents a collection of clustering and decomposition techniques enabling the construction of sparse and locality preserving representations for arbitrary networks. These new clustering techniques have already found several powerful applications in the area of distributed network algorithms. Two of these applications are described in this(More)
Let <i>X=[1,2,&#8226;&#8226;&#8226;,n]</i> be a ground set of <i>n</i> elements, and let <i>S</i> be a family of subsets of <i>X</i>, <i>|S|=m</i>, with a positive cost <i>c<sub>S</sub></i> associated with each <i>S &#8712; S</i>.Consider the following online version of the set cover problem, described as a game between an algorithm and an adversary. An(More)
The essence of the simplest buy-at-bulk network design problem is buying network capacity "whole-sale" to guarantee connectivity from all network nodes to a certain central network switch. Capacity is sold with "volume discount": the more capacity is bought, the cheaper is the price per unit of bandwidth. We provide O(log 2 n) randomized approximation(More)
We introduce a concept of network decomposition, a partitioning of an arbitrary graph into small-diameter connected components, such that the graph created by contracting each component into a single node has low chromatic number and low arboricity. We present an eecient distributed algorithm for constructing such a decomposition, and demonstrate its use(More)