Buffer overflow management in QoS switches
- A. Kesselman, Zvi Lotker, Y. Mansour, B. Patt-Shamir, B. Schieber, M. Sviridenko
- Computer ScienceSymposium on the Theory of Computing
- 6 July 2001
It is proved that the greedy algorithm that drops the earliest packets among all low-value packets is the best greedy algorithm, and the competitive ratio of any online algorithm for a uniform bounded delay buffer is bounded away from 1, independent of the delay size.
Conflict-free colorings of simple geometric regions with applications to frequency assignment in cellular networks
- G. Even, Zvi Lotker, D. Ron, S. Smorodinsky
- MathematicsThe 43rd Annual IEEE Symposium on Foundations of…
- 16 November 2002
It is shown that O(log |X|) colors suffice for set systems in which X is a set of points in the plane and the sets are intersections of X with scaled translations of a convex region.
How to Explore a Fast-Changing World (Cover Time of a Simple Random Walk on Evolving Graphs)
- C. Avin, M. Koucký, Zvi Lotker
- Mathematics, Computer ScienceInternational Colloquium on Automata, Languages…
- 7 July 2008
It is shown that there are adversary strategies which force the expected cover time of a simple random walk on connected dynamic graphs to be exponential, and a simple strategy is provided, the lazyrandom walk, that guarantees polynomial cover time regardless of the changes made by the adversary.
Homophily and the Glass Ceiling Effect in Social Networks
- C. Avin, Barbara Keller, Zvi Lotker, C. Mathieu, D. Peleg, Y. Pignolet
- EconomicsInformation Technology Convergence and Services
- 11 January 2015
This model consists of a network composed of two types of vertices, representing two sub-populations, and accommodates three well known social phenomena: (i) the "rich get richer" mechanism, (ii) a minority-majority partition, and (iii) homophily.
Many random walks are faster than one
- N. Alon, C. Avin, M. Koucký, G. Kozma, Zvi Lotker, M. Tuttle
- Mathematics, Computer ScienceACM Symposium on Parallelism in Algorithms and…
- 3 May 2007
The cover time is studied and it is shown that for a large collection of interesting graphs, running many random walks in parallel yields a speed-up in the cover time that is linear in the number of parallel walks.
Improved Distributed Approximate Matching
- Zvi Lotker, B. Patt-Shamir, Seth Pettie
- Computer Science, MathematicsJournal of the ACM
- 2 November 2015
A distributed network algorithms to compute weighted and unweighted matchings with improved approximation ratios and running times and another algorithm which provides (½-ε) approximation in general graphs in O(logε-1log n) time, improving on the previously known algorithms.
Collaborative search on the plane without communication
- O. Feinerman, Amos Korman, Zvi Lotker, Jean-Sébastien Sereni
- Computer ScienceACM SIGACT-SIGOPS Symposium on Principles of…
- 10 May 2012
The Ants Nearby Treasure Search (ANTS) problem is introduced, a generalization of the classical cow-path problem, which is relevant for collective foraging in animal groups, and a uniform algorithm is proposed that is both efficient and extremely simple, suggesting its relevance for actual biological scenarios.
Many Random Walks Are Faster Than One†
- N. Alon, C. Avin, M. Koucký, G. Kozma, Zvi Lotker, M. Tuttle
- Mathematics, Computer ScienceCombinatorics, probability & computing
- 7 April 2011
The cover time is studied and it is shown that for a large collection of interesting graphs, running many random walks in parallel yields a speed-up in the cover time that is linear in the number of parallel walks.
Nearly optimal FIFO buffer management for DiffServ
- Zvi Lotker, B. Patt-Shamir
- Computer ScienceACM SIGACT-SIGOPS Symposium on Principles of…
- 21 July 2002
An on-line algorithm whose competitive ratio is approximately 1.30 for the worst case α is presented, which is close to the best previous general upper bound of about 1.888.
Distributed MST for constant diameter graphs
- Zvi Lotker, B. Patt-Shamir, D. Peleg
- Computer Science, MathematicsACM SIGACT-SIGOPS Symposium on Principles of…
- 1 August 2001
It is shown that the number of communication rounds necessary to compute a minimum-weight spanning tree (MST) for graphs of constant diameter in the bounded-messages model can be as high as $$\Omega(\sqrt[3]n/\sqrt{B})$$ and $$Omega(-1)n/B)$$, and the asymptotic lower bounds hold for randomized algorithms as well.
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