Service provisioning can be enhanced with spectrally spatially flexible optical networks (SS-FONs) with multicore fibers; however, intercore crosstalk (XT) is a dominant impairment that complicates the problem of maintaining the quality of transmission (QoT) and resource allocation. The selection of modulation formats (MFs), due to their unique XT sensitivities, further increases the complexity. The routing, modulation, core, and spectrum assignment (RMCSA) problem must select the resources carefully to exploit the available capacity while meeting the desired QoT. In this paper, we propose an RMCSA algorithm called the tridental resource assignment (TRA) algorithm for transparent SS-FONs, and its variant, translucency-aware TRA (TaTRA), for translucent SS-FONs. TRA balances three different factors that affect network performance under dynamic resource allocation. We consider translucent networks with flexible regeneration and with and without modulation and spectrum conversion. Our resource assignment approach includes both an offline network planning component to calculate path priorities and an online/dynamic provisioning component to allocate resources. Extensive simulation experiments performed in realistic network scenarios indicate that TRA and TaTRA significantly reduce the bandwidth blocking probability by several orders of magnitude in some cases.
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Delayed spectrum allocation in elastic optical networks with anycast traffic
We investigate the problem of dynamic routing and spectrum assignment for advance reservation anycast requests using a novel algorithm called Delayed Spectrum Allocation (DSA) which delays allocation of resources until immediately before transmission begins. We evaluate the flexible window STSD (demands that specify start-time and duration) to further improve request blocking. Through extensive simulation results, we show that anycast with flexible STSD using DSA approach can significantly reduce blocking probability of anycast and unicast requests compared to traditional Immediate Spectrum Allocation (ISA). The improvement is up to 50 percent in unicast traffic and even higher in anycasting. We also propose balanced routing for anycast algorithms to reduce the blocking.
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- Award ID(s):
- 2008530
- PAR ID:
- 10413967
- Date Published:
- Journal Name:
- OSA Continuum
- Volume:
- 4
- Issue:
- 8
- ISSN:
- 2578-7519
- Page Range / eLocation ID:
- 2118
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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