A New Approach to Loss-Free Packet/Burst Transmission in All-Optical Networks

This work introduces a new approach to get loss-free burst/packet transmission in optical burst and packet switched networks. To this end, our proposal defines (1) a routing and wavelength assignment (RWA) scheme based on the concept of wavelength tree, and (2) a simple contention resolution mechanism that solves contention using a limited number of fiber delay lines. We show that using the proposed scheme, for a 2-link-connected network with n nodes, there exists communication between any pair of nodes with [n/2] wavelengths. We apply this approach to address the problem of finding (conflict-free) transmission schemes in iterated line digraphs. Such digraphs have proved to be very useful models for dense, easily mutable, and fault tolerant communication networks. Examples of such networks are the well-known De Bruijn and Kautz digraphs and the wrapped butterfly networks. Our study leads us to define a useful tool for obtaining wavelength trees. By way of example, we illustrate the scheme operation for the 2-regular Kautz digraph. Simulation results show a good behavior in terms of transmission delay and resources utilization.