Low time complexity algorithms for path computation in Cayley Graphs

• Published in: Discrete Applied Mathematics Vol. 259; pp. 218 - 225
• Main Authors: Aguirre-Guerrero, D., Ducoffe, G., Fàbrega, L., Vilà, P., Coudert, D.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 30.04.2019; Elsevier BV; Elsevier
• Subjects: [formula omitted]-shortest paths; Algorithms; Cayley Graphs; Complexity; Computation; Computer Science; Data Structures and Algorithms; Graphs; Interconnection networks; Networking and Internet Architecture; Path computation; Shortest-path problems; Topology; Word processing; Cayley Graphs; Path computation; K-shortest paths; Interconnection networks; Cayley graphs; interconnection networks; path computation
• ISSN: 0166-218X; 1872-6771; 1872-6771
• DOI: 10.1016/j.dam.2018.12.005

We study the problem of path computation in Cayley Graphs (CG) from an approach of word processing in groups. This approach consists in encoding the topological structure of CG in an automaton called Diff, then techniques of word processing are applied for computing the shortest paths. We present algorithms for computing the K-shortest paths, the shortest disjoint paths and the shortest path avoiding a set of nodes and edges. For any CG with diameter D, the time complexity of the proposed algorithms is O(KD|Diff|), where |Diff| denotes the size of Diff. We show that our proposal outperforms the state of art of topology-agnostic algorithms for disjoint shortest paths and stays competitive with respect to proposals for specific families of CG. Therefore, the proposed algorithms set a base in the design of adaptive and low-complexity routing schemes for networks whose interconnections are defined by CG.