Token management schemes and random walks yield self-stabilizing mutual exclusion
PODC '90 Proceedings of the ninth annual ACM symposium on Principles of distributed computing
SIAM Journal on Control and Optimization
Minimax Rendezvous on the Line
SIAM Journal on Control and Optimization
Asymmetric rendezvous on the plane
Proceedings of the fourteenth annual symposium on Computational geometry
SIAM Journal on Control and Optimization
Agent Rendezvous: A Dynamic Symmetry-Breaking Problem
ICALP '96 Proceedings of the 23rd International Colloquium on Automata, Languages and Programming
Gathering of Asynchronous Oblivious Robots with Limited Visibility
STACS '01 Proceedings of the 18th Annual Symposium on Theoretical Aspects of Computer Science
Operations Research
Two Dimensional Rendezvous Search
Operations Research
Mobile Agent Rendezvous in a Ring
ICDCS '03 Proceedings of the 23rd International Conference on Distributed Computing Systems
Asynchronous deterministic rendezvous in graphs
Theoretical Computer Science
Deterministic Rendezvous in Graphs
Algorithmica
Deterministic rendezvous, treasure hunts and strongly universal exploration sequences
SODA '07 Proceedings of the eighteenth annual ACM-SIAM symposium on Discrete algorithms
External Memory Algorithms for String Problems
Fundamenta Informaticae - Workshop on Combinatorial Algorithms
Deterministic Rendezvous in Trees with Little Memory
DISC '08 Proceedings of the 22nd international symposium on Distributed Computing
Solving the robots gathering problem
ICALP'03 Proceedings of the 30th international conference on Automata, languages and programming
Randomized rendez-vous with limited memory
LATIN'08 Proceedings of the 8th Latin American conference on Theoretical informatics
Delays induce an exponential memory gap for rendezvous in trees
Proceedings of the twenty-second annual ACM symposium on Parallelism in algorithms and architectures
How to meet when you forget: log-space rendezvous in arbitrary graphs
Proceedings of the 29th ACM SIGACT-SIGOPS symposium on Principles of distributed computing
How to meet asynchronously (almost) everywhere
SODA '10 Proceedings of the twenty-first annual ACM-SIAM symposium on Discrete Algorithms
How to meet in anonymous network
SIROCCO'06 Proceedings of the 13th international conference on Structural Information and Communication Complexity
Space-optimal rendezvous of mobile agents in asynchronous trees
SIROCCO'10 Proceedings of the 17th international conference on Structural Information and Communication Complexity
Time of anonymous rendezvous in trees: determinism vs. randomization
SIROCCO'12 Proceedings of the 19th international conference on Structural Information and Communication Complexity
Delays Induce an Exponential Memory Gap for Rendezvous in Trees
ACM Transactions on Algorithms (TALG)
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Two identical (anonymous) mobile agents start from arbitrary nodes of an unknown tree and have to meet at some node. Agents move in synchronous rounds: in each round an agent can either stay at the current node or move to one of its neighbors. We consider deterministic algorithms for this rendezvous task. The main result of this paper is a tight trade-off between the optimal time of completing rendezvous and the size of memory of the agents. For agents with k memory bits, we show that optimal rendezvous time is Θ(n+n2/k) in n-node trees. More precisely, if k ≥ c log n, for some constant c, we design agents accomplishing rendezvous in arbitrary trees of unknown size n in time O(n+n2/k), starting with arbitrary delay. We also show that no pair of agents can accomplish rendezvous in time o(n+n2/k), even in the class of lines of known length and even with simultaneous start. Finally, we prove that at least logarithmic memory is necessary for rendezvous, even for agents starting simultaneously in a n-node line.