A customizable two-step framework for general equipment provisioning in Optical Transport Networks

Optical Transport Network (OTN) is a standard approach to offering transport support to a variety of existing service technologies, e.g., ESCON, HDTV, GE, etc. Multiple service technologies can be concurrently multiplexed onto one common transport network, which offers hierarchical transmission rate wrappers physically supported by Wavelength Division Multiplexing (WDM) lambda channels. Algorithms to perform grooming and routing in OTN are expected to be complicated due to the large number of grooming options that are available in the standard. In addition, these algorithms are likely to be designed by the vendor engineers, who have full knowledge of the grooming, switching, and routing capabilities of their own equipment. Yet the authors of this paper propose a relatively simple algorithm framework for equipment provisioning in OTN that can be customized by the network designer. Taking advantage of the multi-rate nature of supported services in OTN, traffic demands can be divided into two groups based on their bandwidth requirement. Demands with bandwidth request below a bandwidth threshold are placed on newly provisioned resources and demands with bandwidth request above the threshold are preferably routed over already provisioned resources. The latter procedure is more time consuming but yields more efficient traffic grooming when compared to the former procedure. The bandwidth threshold can be set by the network designer either to decrease running time of the algorithm, or conversely, to increase optimality of the solution found.