Impairment-Aware Optical Networking: A Survey

Optimal regenerator placement in translucent optical networks

“…Linear impairments are independent of the signal power and affect each of the wavelengths (optical channels) individually, whereas nonlinear impairments affect not only each optical channel individually but they also cause disturbance and interference between them [5]. Optical reach [2,14] (also called transparent reach [1,5] and transmission reach [8]) is the maximum distance an optical signal can travel before 3R-regeneration is needed. Optical reach is a popular metric [2,8] to determine when 3R regeneration is needed and usually ranges from 2000 to 4000 km [4].…”

“…Henceforth, in this paper, we will call a node which has the capacity to carry out 3R regeneration as a regenerator node. Even though regeneration can be accomplished completely in the optical domain, regeneration in the electronic domain (i.e., using OEO conversion) is still the most economical and reliable technique [8]. When OEO conversion takes place, carrier wavelength conversion is available for free [5,9], so that, if a lightpath from S to D undergoes OEO conversion at some node P, the carrier wavelength of the incoming lightpath to P may be different from the carrier wavelength of the outgoing lightpath from P.…”

“…Optical reach [2,14] (also called transparent reach [1,5] and transmission reach [8]) is the maximum distance an optical signal can travel before 3R-regeneration is needed. Optical reach is a popular metric [2,8] to determine when 3R regeneration is needed and usually ranges from 2000 to 4000 km [4]. 1 A lightpath that involves one or more regenerators is often called a translucent lightpath [1].…”

“…Following [5,8,16], when carrying out network planning, we classify the requests for communication as follows: Route and wavelength assignment where all requests are PLDs (DLDs) are called static, also offline [5,9,10] (dynamic, also on-line [5,9,10]) PLI-RWA. In a translucent network, the PLI-RWA problem will be inevitably coupled with regeneration placement problem [5,[8][9][10] in which the network designers are trying to plan and design, for a given network topology, a translucent network with an optimal number of regeneration sites.…”

Dynamic provisioning of fault tolerant optical networks for data centers

“…Optical reach [18] (also called as transmission reach [24]) is the maximum distance an optical signal can travel before signal regeneration is needed. Longer an optical reach is, lesser is the amount of regeneration needed.…”