Regenerator Placement Strategies for Translucent OBS Networks

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., with optical 3R regeneration) or opaque (i.e., with electrical 3R regeneration) networks. However, both solutions are not feasible due to the technological requirements of the former and the high cost of the latter. In this paper, we deal with a translucent OBS (TL-OBS) network architecture that aims at bridging the gap between the transparent and opaque solutions. In order to evaluate its performance, a formulation of the routing and regenerator placement and dimensioning problem (RRPD) is presented. Since such formulation results in a complex problem, we also propose two alternative strategies. In particular, we evaluate the tradeoff between optimality and execution times provided by these methods. Finally, we conduct a series of simulation experiments that prove that the TL-OBS network model proposed effectively deals with burst losses caused by the impact of PLIs and ensures that the overall network performance remains unaffected.