att_abstract={{Advances in the development of colorless and
non-directional reconfigurable optical add-drop multiplexers
(ROADMs) enable flexible pre-deployment of optoelectronic
regenerators (reshaping, retiming, and reamplifying
known as 3R) in future optical networks. Compared to
the current practice of installing a regenerator only when
a circuit needs them, pre-deployment of regenerators in
specific sites will allow service providers to achieve rapid
provisioning such as Bandwidth-on-Demand (BoD) service
and fast restoration. Concentrating the pre-deployment of
regenerators in a subset of ROADM sites will achieve high
utilization and reduces the network operational costs. We
prove the resulting optimization problem is NP-hard and
provide the proof. We present an efficient heuristic for this
problem that takes into account both the cost of individual
circuits (regenerator cost and transmission line system
cost) and the number of regenerator sites. We validate our
heuristic approach with Integer Linear Programming (ILP)
formulations for a small network. Using specific network
examples we show that our heuristic has near optimal performance
under most studied scenarios and cost models. We
further enhance the heuristic to incorporate the probability
of a demand for each circuit. This enables a reduction in
the number of regenerator sites, by allowing circuits to
use costlier paths if they have low probability of being
needed. We also evaluate the heuristic to determine the extra
regenerator sites required to support diverse routing. In this
paper we provide detailed analysis, pseudocodes, and proofs
for the models previously presented in [1], [2], and compare
the heuristic results with Integer Linear Programming (ILP)
for a small scale network topology.}},
	att_authors={rs5419, ac2182, gl1464, wz1750, sw1213, rd2518, pm1519, bb4341, mf2182},
	att_copyright={{Optical Society of America}},
	att_copyright_notice={{The definitive version was published in  2013 {{, Volume 5}}{{, Issue 11}}{{, 2013-11-01}}
	author={Rakesh Sinha and Angela Chiu and Guangzhi Li and Weiyi Zhang and Sheryl Woodward and Robert Doverspike and Peter Magill and Balagangadhar Bathula and bergman and Mark Feuer},
	institution={{Journal of optical communications and networking (JOCN)}},
	title={{Constraint Routing and Regenerator Site
Concentration in ROADM Networks}},