Modelling and Performance Evaluation of a Translucent OBS Network Architecture

Abstract

Abstract-Most research works in optical burst switching (OBS) networks do not take into account the impact of physical layer impairments (PLIs) either by considering fully transparent (i.e., using optical 3R regeneration) or opaque (i.e., electrical 3R regeneration) networks. However, both solutions are not feasible for different reasons. In this paper, we propose a novel translucent OBS network architecture which aims at bridging the gap between the transparent and opaque solutions. In order to evaluate its performance, two different joint regenerator placement and routing heuristics are provided. Simulation results show that our translucent network model achieves performance results as good as those obtained with an opaque solution but with considerably less regenerators.

RRPD strategies for a T-OBS network architecture

“…In this Section, we first compare the performance of the MILP1 and MILP2/3 problems with that of the LCR algorithm which we proposed in [4]. Then, we study the performance of the T-OBS network under the different RRPD strategies to prove their effectiveness at keeping OSNR losses under control.…”

“…Under the assumption that any burst may access any regenerator in a node (as shown in [4], the architecture proposed allows a fair access to the regenerator pool), we make use of the inverse of the Erlang B-loss function as the dimensioning function f . An straightforward way to implement this dimensioning function is to make use of vector a and Procedure 1, which have been both detailed in Section III-D.…”

“…Here it is worth pointing out that we obtain S p , p ∈ P o by means of a precomputation phase where all possible regeneration options are obtained using the OSNR model presented in [4].…”

“…In [4], we presented a novel T-OBS network which consists of all-optical core switching nodes built according to the wellknown tune-and-select (TAS) [1] architecture. These nodes may also be equipped with electrical regenerators according to the decision of the RRPD strategies considered.…”

“…Among the optical switching paradigms, OBS has emerged as a competitive choice for the transmission of highly dynamic data traffic in the near future. Accordingly, in [4], we presented a novel translucent OBS (T-OBS) network architecture in which core nodes switch incoming data bursts to their output ports either in an all-optical fashion or through O/E/O regenerators when signal regeneration is required. Indeed, O/E/O regenerators are sparsely deployed across the network according to the decision of routing and regenerator placement and dimensioning (RRPD) heuristics which take into account the optical signal to noise ratio (OSNR) at the receiving end as the signal quality performance indicator.…”