Result: Constructions of sparse asymmetric connectors with number theoretic methods

Title:
Constructions of sparse asymmetric connectors with number theoretic methods
Source:
Networks (New York, NY). 45(3):119-124
Publisher Information:
New York, NY: John Wiley & Sons, 2005.
Publication Year:
2005
Physical Description:
print, 15 ref
Original Material:
INIST-CNRS
Document Type:
Academic journal Article
File Description:
text
Language:
English
Author Affiliations:
Mathematisches Seminar, Christian-Albrechts-Universitat zu Kiel, Christian-Albrechts-Platz 4, 24118 Kiel, Germany
ISSN:
0028-3045
Rights:
Copyright 2005 INIST-CNRS
CC BY 4.0
Sauf mention contraire ci-dessus, le contenu de cette notice bibliographique peut être utilisé dans le cadre d’une licence CC BY 4.0 Inist-CNRS / Unless otherwise stated above, the content of this bibliographic record may be used under a CC BY 4.0 licence by Inist-CNRS / A menos que se haya señalado antes, el contenido de este registro bibliográfico puede ser utilizado al amparo de una licencia CC BY 4.0 Inist-CNRS
Notes:
Telecommunications and information theory
Accession Number:
edscal.16712334
Database:
PASCAL Archive

Further Information

We consider the problem of connecting a set 1 of n inputs to a set O of N outputs (n≤N) by as few edges as possible such that for every injective mapping f: I → O there are n vertex disjoint paths from i to f(i) of length k for a given k e IN. For k = Ω(log N + log2 n) Oruç (J Parallet Distributed Comput 1994, 359-366 [10]) gave the presently best (n, N)-connector with O(N+ n . log n) edges. For κ = 2 and N the square of a prime, Richards and Hwang (1985) described a construction using N[√n+5/4 - 1/2] +n [√n+5/4- 1/2]√N edges. We show by a probabilistic argument that an optimal (n,N)-connector has Θ(N) edges, if n ≤ N1 2-ε for some ∈ > 0. Moreover, we give explicit constructions based on a new number theoretic approach that need at most N3n/4 + 2n 3n/4 N edges for arbitrary choices of n and N. The improvement we achieve is based on applying a generalization of the Erdös-Heilbronn conjecture on the size of restricted sums.