Abstract
Fraigniaud et al. (2006) introduced a new measure of difficulty for a distributed task in a network. The smallest number of bits of advice of a distributed problem is the smallest number of bits of information that has to be available to nodes in order to accomplish the task efficiently. Our paper deals with the number of bits of advice required to perform efficiently the graph searching problem in a distributed setting. In this variant of the problem, all searchers are initially placed at a particular node of the network. The aim of the team of searchers is to capture an invisible and arbitrarily fast fugitive in a monotone connected way, i.e., the cleared part of the graph is permanently connected, and never decreases while the search strategy is executed. We show that the minimum number of bits of advice permitting the monotone connected clearing of a network in a distributed setting is O (n logn), where n is the number of nodes of the network, and this bound is tight. More precisely, we first provide a labelling of the vertices of any graph G, using a total of O(n logn) bits, and a protocol using this labelling that enables clearing G in a monotone connected distributed way. Then, we show that this number of bits of advice is almost optimal: no protocol using an oracle providing o(n logn) bits of advice permits the monotone connected clearing of a network using the smallest number of searchers.
Preview
Unable to display preview. Download preview PDF.
Similar content being viewed by others
References
Barrière, L., et al.: Capture of an intruder by mobile agents. In: 14th ACM Symp. on Parallel Algorithms and Architectures (SPAA), pp. 200–209 (2002)
Barrière, L., et al.: Connected and Internal Graph Searching. In: Bodlaender, H.L. (ed.) WG 2003. LNCS, vol. 2880, pp. 34–45. Springer, Heidelberg (2003)
Bender, M.A., et al.: The power of a pebble: Exploring and mapping directed graphs. Information and Computation 176, 1–21 (2002)
Bienstock, D.: Graph searching, path-width, tree-width and related problems (a survey). In: DIMACS Ser. in Discrete Mathematics and Theoretical Computer Science, vol. 5, pp. 33–49 (1991)
Bienstock, D., Seymour, P.: Monotonicity in graph searching. Journal of Algorithms 12, 239–245 (1991)
Blin, L., et al.: Distributing Chasing of Network Intruders. In: Flocchini, P., Gąsieniec, L. (eds.) SIROCCO 2006. LNCS, vol. 4056, pp. 70–84. Springer, Heidelberg (2006)
Breisch, R.: An intuitive approach to speleotopology. Southwestern Cavers VI(5), 72–78 (1967)
Clementi, A.E.F., Monti, A., Silvestri, R.: Selective families, superimposed codes, and broadcasting on unknown radio networks. In: 12th Ann. ACM-SIAM Symp. on Discrete Algorithms (SODA), pp. 709–718 (2001)
Fich, F., Ruppert, E.: Hundreds of impossibility results for distributed computing. Distributed Computing 16, 121–163 (2003)
Flocchini, P., Luccio, F.L., Song, L.: Decontamination of chordal rings and tori. In: Proc. of 8th Workshop on Advances in Parallel and Distributed Computational Models (APDCM) (2006)
Flocchini, P., Huang, M.J., Luccio, F.L.: Contiguous search in the hypercube for capturing an intruder. In: Proc. of 18th IEEE Int. Parallel and Distributed Processing Symp (IPDPS) (2005)
Fraigniaud, P., Ilcinkas, D., Pelc, A.: Oracle Size: a New Measure of Difficulty for Communication Tasks. In: 25th Annual ACM Symp. on Principles of Distributed Computing (PODC), pp. 179–187 (2006)
Fraigniaud, P., Ilcinkas, D., Pelc, A.: Tree Exploration with an Oracle. In: Královič, R., Urzyczyn, P. (eds.) MFCS 2006. LNCS, vol. 4162, pp. 24–37. Springer, Heidelberg (2006)
Fraigniaud, P., Nisse, N.: Connected Treewidth and Connected Graph Searching. In: Correa, J.R., Hevia, A., Kiwi, M. (eds.) LATIN 2006. LNCS, vol. 3887, pp. 470–490. Springer, Heidelberg (2006)
LaPaugh, A.: Recontamination does not help to search a graph. Journal of the ACM 40(2), 224–245 (1993)
Megiddo, N., et al.: The complexity of searching a graph. Journal of the ACM 35(1), 18–44 (1988)
Nisse, N., Soguet, D.: Graph searching with advice. Technical Report LRI-1469, University Paris-Sud, France (March 2007)
Parson, T.: Pursuit-evasion in a graph. In: Theory and Applications of Graphs. Lecture Notes in Mathematics, vol. 642, pp. 426–441. Springer, Heidelberg (1978)
Seymour, P., Thomas, R.: Graph searching and a min-max theorem for tree-width. J. Combin. Theory Ser. B. 58, 22–33 (1993)
Yang, B., Dyer, D., Alspach, B.: Sweeping Graphs with Large Clique Number. In: Fleischer, R., Trippen, G. (eds.) ISAAC 2004. LNCS, vol. 3341, pp. 908–920. Springer, Heidelberg (2004)
Author information
Authors and Affiliations
Editor information
Rights and permissions
Copyright information
© 2007 Springer Berlin Heidelberg
About this paper
Cite this paper
Nisse, N., Soguet, D. (2007). Graph Searching with Advice. In: Prencipe, G., Zaks, S. (eds) Structural Information and Communication Complexity. SIROCCO 2007. Lecture Notes in Computer Science, vol 4474. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-540-72951-8_6
Download citation
DOI: https://doi.org/10.1007/978-3-540-72951-8_6
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-540-72918-1
Online ISBN: 978-3-540-72951-8
eBook Packages: Computer ScienceComputer Science (R0)