Abstract
We study the singlemessage broadcast problem in dynamic radio networks. We show that the time complexity of the problem depends on the amount of stability and connectivity of the dynamic network topology and on the adaptiveness of the adversary providing the dynamic topology. More formally, we model communication using the standard graphbased radio network model. To model the dynamic network, we use a variant of the synchronous dynamic graph model introduced in [Kuhn et al., STOC 2010]. For integer parameters T >= 1 and k => 1, we call a dynamic graph Tinterval kconnected if for every interval of T consecutive rounds, there exists a kvertexconnected stable subgraph. Further, for an integer parameter tau >= 0, we say that the adversary providing the dynamic network is tauoblivious if for constructing the graph of some round t, the adversary has access to all the randomness (and states) of the algorithm up to round ttau.
As our main result, we show that for any T >= 1, any k >= 1, and any tau = 1, for a tauoblivious adversary, there is a distributed algorithm to broadcast a single message in time O((1+n/(k * min(tau,T)) * n *log^3(n)). We further show that even for large interval kconnectivity, efficient broadcast is not possible for the usual adaptive adversaries. For a 1oblivious adversary, we show that even for any T <= (n/k)^{1epsilon} (for any constant epsilon > 0) and for any k >= 1, global broadcast in Tinterval kconnected networks requires at least Omega(n^2/k^2*log(n)) time. Further, for a 0oblivious adversary, broadcast cannot be solved in Tinterval kconnected networks as long as T < nk.
BibTeX  Entry
@InProceedings{ahmadi_et_al:LIPIcs:2016:6598,
author = {Mohamad Ahmadi and Abdolhamid Ghodselahi and Fabian Kuhn and Anisur Rahaman Molla},
title = {{The Cost of Global Broadcast in Dynamic Radio Networks}},
booktitle = {19th International Conference on Principles of Distributed Systems (OPODIS 2015)},
pages = {117},
series = {Leibniz International Proceedings in Informatics (LIPIcs)},
ISBN = {9783939897989},
ISSN = {18688969},
year = {2016},
volume = {46},
editor = {Emmanuelle Anceaume and Christian Cachin and Maria PotopButucaru},
publisher = {Schloss DagstuhlLeibnizZentrum fuer Informatik},
address = {Dagstuhl, Germany},
URL = {http://drops.dagstuhl.de/opus/volltexte/2016/6598},
URN = {urn:nbn:de:0030drops65989},
doi = {10.4230/LIPIcs.OPODIS.2015.7},
annote = {Keywords: radio network, dynamic network, global broadcast, interval connectivity, hitting game}
}
Keywords: 

radio network, dynamic network, global broadcast, interval connectivity, hitting game 
Collection: 

19th International Conference on Principles of Distributed Systems (OPODIS 2015) 
Issue Date: 

2016 
Date of publication: 

13.10.2016 