Exploring and Making Safe Dangerous Networks Using Mobile Entities

  • Mattia D’Emidio
  • Daniele Frigioni
  • Alfredo Navarra
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7960)


We consider synchronous and mobile entities that have to explore and make safe a network with faulty nodes, called black-holes, that destroy any entering entity. We are interested in the scenario where the destruction of an entity by means of a black-hole also affects all the entities within a fixed range r (in terms of hops), and we ask for the minimum number of synchronized steps needed to remove all the black-holes from that network. Clearly, if there are b black-holes in the network, then k ≥ b entities are necessary.

First, we show that the problem is NP-hard even for b = k = 1; second, we provide an asymptotical optimal solution for the case of r = 0 and a general lower bound for the case of r > 0; third, we propose two different strategies plus a refined heuristic for the case of r = 1, and we prove they are all asymptotically optimal; finally, we provide an experimental study to show the practical performance of the proposed strategies.


Black Hole Mobile Agent Hamiltonian Path Input Graph Exploration Strategy 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Mattia D’Emidio
    • 1
  • Daniele Frigioni
    • 1
  • Alfredo Navarra
    • 2
  1. 1.Department of Information Engineering, Computer Science and MathematicsUniversity of L’AquilaL’AquilaItaly
  2. 2.Department of Mathematics and Computer ScienceUniversity of PerugiaPerugiaItaly

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