Search Results

Documents authored by Schneider, Philipp


Document
Routing Schemes and Distance Oracles in the Hybrid Model

Authors: Fabian Kuhn and Philipp Schneider

Published in: LIPIcs, Volume 246, 36th International Symposium on Distributed Computing (DISC 2022)


Abstract
The HYBRID model was introduced as a means for theoretical study of distributed networks that use various communication modes. Conceptually, it is a synchronous message passing model with a local communication mode, where in each round each node can send large messages to all its neighbors in a local network (a graph), and a global communication mode, where each node is allotted limited (polylogarithmic) bandwidth per round to communicate with any node in the network. Prior work has often focused on shortest paths problems in the local network, as their global nature makes these an interesting case study how combining communication modes in the HYBRID model can overcome the individual lower bounds of either mode. In this work we consider a similar problem, namely computation of distance oracles and routing schemes. In the former, all nodes have to compute local tables, which allows them to look up the distance (estimates) to any target node in the local network when provided with the label of the target. In the latter, it suffices that nodes give the next node on an (approximately) shortest path to the target. Our goal is to compute these local tables as fast as possible with labels as small as possible. We show that this can be done exactly in Õ(n^{1/3}) communication rounds and labels of size Θ(n^{2/3}) bits. For constant stretch approximations we achieve labels of size O(log n) in the same time. Further, as our main technical contribution, we provide computational lower bounds for a variety of problem parameters. For instance, we show that computing solutions with stretch below a certain constant takes Ω̃(n^{1/3}) rounds even for labels of size O(n^{2/3}).

Cite as

Fabian Kuhn and Philipp Schneider. Routing Schemes and Distance Oracles in the Hybrid Model. In 36th International Symposium on Distributed Computing (DISC 2022). Leibniz International Proceedings in Informatics (LIPIcs), Volume 246, pp. 28:1-28:22, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2022)


Copy BibTex To Clipboard

@InProceedings{kuhn_et_al:LIPIcs.DISC.2022.28,
  author =	{Kuhn, Fabian and Schneider, Philipp},
  title =	{{Routing Schemes and Distance Oracles in the Hybrid Model}},
  booktitle =	{36th International Symposium on Distributed Computing (DISC 2022)},
  pages =	{28:1--28:22},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-255-6},
  ISSN =	{1868-8969},
  year =	{2022},
  volume =	{246},
  editor =	{Scheideler, Christian},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.DISC.2022.28},
  URN =		{urn:nbn:de:0030-drops-172198},
  doi =		{10.4230/LIPIcs.DISC.2022.28},
  annote =	{Keywords: Distributed Computing, Graph Algorithms, Complexity Analysis}
}
Document
Near-Shortest Path Routing in Hybrid Communication Networks

Authors: Sam Coy, Artur Czumaj, Michael Feldmann, Kristian Hinnenthal, Fabian Kuhn, Christian Scheideler, Philipp Schneider, and Martijn Struijs

Published in: LIPIcs, Volume 217, 25th International Conference on Principles of Distributed Systems (OPODIS 2021)


Abstract
Hybrid networks, i.e., networks that leverage different means of communication, become ever more widespread. To allow theoretical study of such networks, [Augustine et al., SODA'20] introduced the HYBRID model, which is based on the concept of synchronous message passing and uses two fundamentally different principles of communication: a local mode, which allows every node to exchange one message per round with each neighbor in a local communication graph; and a global mode where any pair of nodes can exchange messages, but only few such exchanges can take place per round. A sizable portion of the previous research for the HYBRID model revolves around basic communication primitives and computing distances or shortest paths in networks. In this paper, we extend this study to a related fundamental problem of computing compact routing schemes for near-shortest paths in the local communication graph. We demonstrate that, for the case where the local communication graph is a unit-disc graph with n nodes that is realized in the plane and has no radio holes, we can deterministically compute a routing scheme that has constant stretch and uses labels and local routing tables of size O(log n) bits in only O(log n) rounds.

Cite as

Sam Coy, Artur Czumaj, Michael Feldmann, Kristian Hinnenthal, Fabian Kuhn, Christian Scheideler, Philipp Schneider, and Martijn Struijs. Near-Shortest Path Routing in Hybrid Communication Networks. In 25th International Conference on Principles of Distributed Systems (OPODIS 2021). Leibniz International Proceedings in Informatics (LIPIcs), Volume 217, pp. 11:1-11:23, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2022)


Copy BibTex To Clipboard

@InProceedings{coy_et_al:LIPIcs.OPODIS.2021.11,
  author =	{Coy, Sam and Czumaj, Artur and Feldmann, Michael and Hinnenthal, Kristian and Kuhn, Fabian and Scheideler, Christian and Schneider, Philipp and Struijs, Martijn},
  title =	{{Near-Shortest Path Routing in Hybrid Communication Networks}},
  booktitle =	{25th International Conference on Principles of Distributed Systems (OPODIS 2021)},
  pages =	{11:1--11:23},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-219-8},
  ISSN =	{1868-8969},
  year =	{2022},
  volume =	{217},
  editor =	{Bramas, Quentin and Gramoli, Vincent and Milani, Alessia},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.OPODIS.2021.11},
  URN =		{urn:nbn:de:0030-drops-157863},
  doi =		{10.4230/LIPIcs.OPODIS.2021.11},
  annote =	{Keywords: Hybrid networks, overlay networks}
}
Document
Broadcasting in an Unreliable SINR Model

Authors: Fabian Kuhn and Philipp Schneider

Published in: LIPIcs, Volume 95, 21st International Conference on Principles of Distributed Systems (OPODIS 2017)


Abstract
We investigate distributed algorithms for broadcasting in unreliable wireless networks. Our basic setting is the signal to noise and interference ratio (SINR) model, which captures the physical key characteristics of wireless communication. We consider a dynamic variant of this model in which an adversary can adaptively control the model parameters for each individual transmission. Moreover, we assume that the network devices have no information about the geometry or the topology of the network and do neither know the exact model parameters nor do they have any control over them. Our model is intended to capture the inherently unstable and unreliable nature of real wireless transmission, where signal quality and reception depends on many different aspects that are often hard to measure or predict. We show that with moderate adaptations, the broadcast algorithm of Daum et al. [DISC 13] also works in such an adversarial, much more dynamic setting. The algorithm allows to broadcast a single message in a network of size n in time O(D·polylog(n+R)), where D is the diameter and R describes the granularity of the communication graph.

Cite as

Fabian Kuhn and Philipp Schneider. Broadcasting in an Unreliable SINR Model. In 21st International Conference on Principles of Distributed Systems (OPODIS 2017). Leibniz International Proceedings in Informatics (LIPIcs), Volume 95, pp. 3:1-3:21, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2018)


Copy BibTex To Clipboard

@InProceedings{kuhn_et_al:LIPIcs.OPODIS.2017.3,
  author =	{Kuhn, Fabian and Schneider, Philipp},
  title =	{{Broadcasting in an Unreliable SINR Model}},
  booktitle =	{21st International Conference on Principles of Distributed Systems (OPODIS 2017)},
  pages =	{3:1--3:21},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-061-3},
  ISSN =	{1868-8969},
  year =	{2018},
  volume =	{95},
  editor =	{Aspnes, James and Bessani, Alysson and Felber, Pascal and Leit\~{a}o, Jo\~{a}o},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.OPODIS.2017.3},
  URN =		{urn:nbn:de:0030-drops-86247},
  doi =		{10.4230/LIPIcs.OPODIS.2017.3},
  annote =	{Keywords: radio networks, wireless networks, broadcast, SINR model, unreliable communication, dynamic networks}
}
Questions / Remarks / Feedback
X

Feedback for Dagstuhl Publishing


Thanks for your feedback!

Feedback submitted

Could not send message

Please try again later or send an E-mail