TY - GEN
T1 - Efficient Dispersion on an Anonymous Ring in the Presence of Weak Byzantine Robots
AU - Molla, Anisur Rahaman
AU - Mondal, Kaushik
AU - Moses, William K.
N1 - Publisher Copyright:
© 2020, Springer Nature Switzerland AG.
PY - 2020/1/1
Y1 - 2020/1/1
N2 - The problem of dispersion of mobile robots on a graph asks that n robots initially placed arbitrarily on the nodes of an n-node anonymous graph, autonomously move to reach a final configuration where exactly each node has at most one robot on it. This problem has been relatively well-studied when robots are non-faulty. In this paper, we introduce the notion of Byzantine faults to this problem, i.e., we formalize the problem of dispersion in the presence of up to f Byzantine robots. We then study the problem on a ring while simultaneously optimizing the time complexity of algorithms and the memory requirement per robot. Specifically, we design deterministic algorithms that attempt to match the time lower bound (rounds) and memory lower bound (bits per robot). Our main result is a deterministic algorithm that is both time and memory optimal, i.e., O(n) rounds and bits of memory required per robot, subject to certain constraints. We subsequently provide results that require less assumptions but are either only time or memory optimal but not both. We also provide a primitive that takes robots initially gathered at a node of the ring and disperses them in a time and memory optimal manner without additional assumptions required.
AB - The problem of dispersion of mobile robots on a graph asks that n robots initially placed arbitrarily on the nodes of an n-node anonymous graph, autonomously move to reach a final configuration where exactly each node has at most one robot on it. This problem has been relatively well-studied when robots are non-faulty. In this paper, we introduce the notion of Byzantine faults to this problem, i.e., we formalize the problem of dispersion in the presence of up to f Byzantine robots. We then study the problem on a ring while simultaneously optimizing the time complexity of algorithms and the memory requirement per robot. Specifically, we design deterministic algorithms that attempt to match the time lower bound (rounds) and memory lower bound (bits per robot). Our main result is a deterministic algorithm that is both time and memory optimal, i.e., O(n) rounds and bits of memory required per robot, subject to certain constraints. We subsequently provide results that require less assumptions but are either only time or memory optimal but not both. We also provide a primitive that takes robots initially gathered at a node of the ring and disperses them in a time and memory optimal manner without additional assumptions required.
KW - Byzantine faults
KW - Dispersion
KW - Distributed algorithm
KW - Faulty robots
KW - Mobile robots
KW - Rings
UR - http://www.scopus.com/inward/record.url?scp=85096479808&partnerID=8YFLogxK
U2 - 10.1007/978-3-030-62401-9_11
DO - 10.1007/978-3-030-62401-9_11
M3 - Conference contribution
AN - SCOPUS:85096479808
SN - 9783030624002
T3 - Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
SP - 154
EP - 169
BT - Algorithms for Sensor Systems - 16th International Symposium on Algorithms and Experiments for Wireless Sensor Networks, ALGOSENSORS 2020, Revised Selected Papers
A2 - Pinotti, Cristina M.
A2 - Navarra, Alfredo
A2 - Bagchi, Amitabha
PB - Springer Science and Business Media Deutschland GmbH
T2 - 16th International Symposium on Algorithms and Experiments for Wireless Sensor Networks, ALGOSENSORS 2020
Y2 - 9 September 2020 through 10 September 2020
ER -