Topics in Distributed Algorithms: On Wireless Networks, Distributed Storage and Streaming
Doktorsavhandling, 2017

Distributed algorithms are executed on a set of computational instances. We refer to these instances as nodes. Nodes are running concurrently and are independent from each other. Furthermore, they have their own instructions and information. In this context, the challenges are to show that the algorithm is correct, regardless of computational, or communication delays and to show bounds on the usage of communication. We are especially interested the behaviour after transient faults and under the existence of Byzantine nodes. This thesis discusses fundamental communication models for distributed algorithms. These models are implementing abstract communication methods. First, we address medium access control for a wireless medium with guarantees on the communication delay. We discuss time division multiple access (TDMA) protocols for ad-hoc networks and we introduce an algorithm that creates a TDMA schedule without using external references for localisation, or time. We justify our algorithm by experimental results. The second topic is the emulation of shared memory on message passing networks. Both, shared memory and message passing are basic interprocessor communication models for distributed algorithms. We are providing a way of emulating shared memory on top of an existing message passing network under the presence of data corruption and stop-failed nodes. Additionally, we ensure the privacy of the data that is stored in the shared memory. The third topic looks into streaming algorithms and optimisation. We study the problem of sorting a stream ofvehicles on a highway with several lanes so that each vehicle reaches its target lane. We look into optimality in terms of minimising the number of move operations, as well as, minimising the length of the output stream. We present an exact algorithm for the case of two lanes and show that NP-Hardness for a increasing number of lanes.

Message Passing

Time Division Multiple Access

Distributed Algorithm


Wireless Networks



Shared Memory



EA, Rännvägen 6, Chalmers
Opponent: Volker Turau, Hamburg University of Technology, Germany


Thomas Petig

Chalmers, Data- och informationsteknik, Nätverk och system

Self-stabilizing TDMA algorithms for wireless ad-hoc networks without external reference

13th Annual Mediterranean Ad Hoc Networking Workshop, MED-HOC-NET 2014, Piran, Slovenia, 2-4 June 2014,; (2014)p. 87-94

Paper i proceeding

Robust and Private Distributed Shared Atomic Memory in Message Passing Networks

Proceedings of the 2015 ACM Symposium on Principles of Distributed Computing,; (2015)p. 311-313

Paper i proceeding

DecTDMA: A Decentralized-TDMA with Link Quality Estimation for WSNs

Lecture Notes in Computer Science,; Vol. 10083(2016)p. 231-247

Paper i proceeding

Thomas Petig, Elad M. Schiller and Jukka Suomela: Changing Lanes on a Highway







Doktorsavhandlingar vid Chalmers tekniska högskola. Ny serie: 4354


Chalmers tekniska högskola

EA, Rännvägen 6, Chalmers

Opponent: Volker Turau, Hamburg University of Technology, Germany