@article{3872,
abstract = {This paper considers the problem of how to efficiently share a wireless medium which is subject to harsh external interference or even jamming. So far, this problem is understood only in simplistic single-hop or unit disk graph models. We in this paper initiate the study of MAC protocols for the SINR interference model (a.k.a. physical model). This paper makes two contributions. First, we introduce a new adversarial SINR model which captures a wide range of interference phenomena. Concretely, we consider a powerful, adaptive adversary which can jam nodes at arbitrary times and which is only limited by some energy budget. Our second contribution is a distributed MAC protocol called Sade which provably achieves a constant competitive throughput in this environment: we show that, with high probability, the protocol ensures that a constant fraction of the non-blocked time periods is used for successful transmissions.},
author = {Ogierman, Adrian and Richa, Andrea and Scheideler, Christian and Schmid, Stefan and Zhang, Jin},
issn = {0178-2770},
journal = {Distributed Computing},
number = {3},
pages = {241--254},
publisher = {Springer Nature},
title = {{Sade: competitive MAC under adversarial SINR}},
doi = {10.1007/s00446-017-0307-1},
volume = {31},
year = {2017},
}
@inproceedings{1815,
author = {J. Daymude, Joshua and Gmyr, Robert and W. Richa, Andrea and Scheideler, Christian and Strothmann, Thim Frederik},
booktitle = {Algorithms for Sensor Systems - 13th International Symposium on Algorithms and Experiments for Wireless Sensor Networks, ALGOSENSORS 2017, Vienna, Austria, September 7-8, 2017, Revised Selected Papers},
pages = {127----140},
title = {{Improved Leader Election for Self-organizing Programmable Matter}},
doi = {10.1007/978-3-319-72751-6_10},
year = {2017},
}
@article{1812,
author = {Koutsopoulos, Andreas and Scheideler, Christian and Strothmann, Thim Frederik},
journal = {Inf. Comput.},
pages = {408----424},
title = {{Towards a universal approach for the finite departure problem in overlay networks}},
doi = {10.1016/j.ic.2016.12.006},
year = {2017},
}
@inproceedings{3422,
abstract = {We study the consensus problem in a synchronous distributed system of n nodes under an adaptive adversary that has a slightly outdated view of the system and can block all incoming and outgoing communication of a constant fraction of the nodes in each round. Motivated by a result of Ben-Or and Bar-Joseph (1998), showing that any consensus algorithm that is resilient against a linear number of crash faults requires $\tilde \Omega(\sqrt n)$ rounds in an n-node network against an adaptive adversary, we consider a late adaptive adversary, who has full knowledge of the network state at the beginning of the previous round and unlimited computational power, but is oblivious to the current state of the nodes.
Our main contributions are randomized distributed algorithms that achieve consensus with high probability among all except a small constant fraction of the nodes (i.e., "almost-everywhere'') against a late adaptive adversary who can block up to ε n$ nodes in each round, for a small constant ε >0$. Our first protocol achieves binary almost-everywhere consensus and also guarantees a decision on the majority input value, thus ensuring plurality consensus. We also present an algorithm that achieves the same time complexity for multi-value consensus. Both of our algorithms succeed in $O(log n)$ rounds with high probability, thus showing an exponential gap to the $\tilde\Omega(\sqrt n)$ lower bound of Ben-Or and Bar-Joseph for strongly adaptive crash-failure adversaries, which can be strengthened to $\Omega(n)$ when allowing the adversary to block nodes instead of permanently crashing them. Our algorithms are scalable to large systems as each node contacts only an (amortized) constant number of peers in each communication round. We show that our algorithms are optimal up to constant (resp.\ sub-logarithmic) factors by proving that every almost-everywhere consensus protocol takes $\Omega(log_d n)$ rounds in the worst case, where d is an upper bound on the number of communication requests initiated per node in each round. We complement our theoretical results with an experimental evaluation of the binary almost-everywhere consensus protocol revealing a short convergence time even against an adversary blocking a large fraction of nodes.},
author = {Robinson, Peter and Scheideler, Christian and Setzer, Alexander},
booktitle = {Proceedings of the 30th ACM Symposium on Parallelism in Algorithms and Architectures (SPAA)},
isbn = {978-1-4503-5799-9/18/07},
keyword = {distributed consensus, randomized algorithm, adaptive adversary, complexity lower bound},
location = {Wien},
title = {{Breaking the $\tilde\Omega(\sqrt{n})$ Barrier: Fast Consensus under a Late Adversary}},
doi = {10.1145/3210377.3210399},
year = {2018},
}
@inproceedings{5764,
author = {Gmyr, Robert and Hinnenthal, Kristian and Kostitsyna, Irina and Kuhn, Fabian and Rudolph, Dorian and Scheideler, Christian and Strothmann, Thim Frederik},
booktitle = {Proceedings of the 24th International Conference on DNA Computing and Molecular Programming},
pages = {122--138},
publisher = {Springer International Publishing},
title = {{Forming Tile Shapes with Simple Robots}},
doi = {10.1007/978-3-030-00030-1_8},
year = {2018},
}
@inproceedings{5985,
author = {Scheideler, Christian},
booktitle = {Proceedings of the 2018 Workshop on Theory and Practice for Integrated Cloud, Fog and Edge Computing Paradigms, TOPIC@PODC 2018, Egham, United Kingdom, July 27, 2018},
pages = {1--2},
title = {{Relays: Towards a Link Layer for Robust and Secure Fog Computing}},
doi = {10.1145/3229774.3229781},
year = {2018},
}
@inproceedings{4351,
abstract = { We extend the concept of monotonic searchability~\cite{DBLP:conf/opodis/ScheidelerSS15}~\cite{DBLP:conf/wdag/ScheidelerSS16} for self-stabilizing systems from one to multiple dimensions.
A system is self-stabilizing if it can recover to a legitimate state from any initial illegal state.
These kind of systems are most often used in distributed applications.
Monotonic searchability provides guarantees when searching for nodes while the recovery process is going on.
More precisely, if a search request started at some node $u$ succeeds in reaching its destination $v$, then all future search requests from $u$ to $v$ succeed as well.
Although there already exists a self-stabilizing protocol for a two-dimensional topology~\cite{DBLP:journals/tcs/JacobRSS12} and an universal approach for monotonic searchability~\cite{DBLP:conf/wdag/ScheidelerSS16}, it is not clear how both of these concepts fit together effectively.
The latter concept even comes with some restrictive assumptions on messages, which is not the case for our protocol.
We propose a simple novel protocol for a self-stabilizing two-dimensional quadtree that satisfies monotonic searchability.
Our protocol can easily be extended to higher dimensions and offers routing in $\mathcal O(\log n)$ hops for any search request.
},
author = {Feldmann, Michael and Kolb, Christina and Scheideler, Christian},
booktitle = {Proceedings of the 20th International Symposium on Stabilization, Safety, and Security of Distributed Systems (SSS)},
pages = {16--31 },
publisher = {Springer, Cham},
title = {{Self-stabilizing Overlays for high-dimensional Monotonic Searchability}},
doi = {10.1007/978-3-030-03232-6_2},
volume = {11201},
year = {2018},
}
@inproceedings{4565,
author = {Jung, Daniel and Kolb, Christina and Scheideler, Christian and Sundermeier, Jannik},
booktitle = {Proceedings of the 30th on Symposium on Parallelism in Algorithms and Architectures (SPAA)},
isbn = {9781450357999},
location = {Wien},
publisher = {ACM Press},
title = {{Brief Announcement: Competitive Routing in Hybrid Communication Networks}},
doi = {10.1145/3210377.3210663},
year = {2018},
}
@inproceedings{5222,
abstract = {We present a self-stabilizing protocol for an overlay network that constructs the Minimum Spanning Tree (MST) for an underlay that is modeled by a weighted tree. The weight of an overlay edge between two nodes is the weighted length of their shortest path in the tree. We rigorously prove that our protocol works correctly under asynchronous and non-FIFO message delivery. Further, the protocol stabilizes after O(N^2) asynchronous rounds where N is the number of nodes in the overlay. },
author = {Götte, Thorsten and Scheideler, Christian and Setzer, Alexander},
booktitle = {Proceedings of the 20th International Symposium on Stabilization, Safety, and Security of Distributed Systems (SSS 2018)},
location = {Tokyo, Japan},
pages = {50--64},
publisher = {Springer},
title = {{On Underlay-Aware Self-Stabilizing Overlay Networks}},
volume = {11201},
year = {2018},
}
@inproceedings{5986,
author = {Gmyr, Robert and Hinnenthal, Kristian and Kostitsyna, Irina and Kuhn, Fabian and Rudolph, Dorian and Scheideler, Christian},
booktitle = {43rd International Symposium on Mathematical Foundations of Computer Science, MFCS 2018, August 27-31, 2018, Liverpool, UK},
pages = {52:1--52:15},
title = {{Shape Recognition by a Finite Automaton Robot}},
doi = {10.4230/LIPIcs.MFCS.2018.52},
year = {2018},
}