{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:12:14Z","timestamp":1760242334506,"version":"build-2065373602"},"reference-count":27,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2017,5,23]],"date-time":"2017-05-23T00:00:00Z","timestamp":1495497600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Future Internet"],"abstract":"<jats:p>This paper provides an initial introduction to, and definition of, the \u2018Dynamically Powered Relays for a Flexible Optical Network\u2019 (DPR-FON) problem for opto-electro-optical (OEO) regenerators used in optical networks. In such networks, optical transmission parameters can be varied dynamically as traffic patterns change. This will provide different bandwidths, but also change the regeneration limits as a result. To support this flexibility, OEOs (\u2018relays\u2019) may be switched on and off as required, thus saving power. DPR-FON is shown to be NP-complete; consequently, solving such a dynamic problem in real-time requires a fast heuristic capable of delivering an acceptable approximation to the optimal configuration with low complexity. In this paper, just such an algorithm is developed, implemented, and evaluated against more computationally-demanding alternatives for two known cases. A number of real-world extensions are considered as the paper develops, combining to produce the \u2018Generalised Dynamically Powered Relays for a Flexible Optical Network\u2019 (GDPR-FON) problem. This, too, is analysed and an associated fast heuristic proposed, along with an exploration of the further research that is required.<\/jats:p>","DOI":"10.3390\/fi9020018","type":"journal-article","created":{"date-parts":[[2017,5,23]],"date-time":"2017-05-23T11:14:33Z","timestamp":1495538073000},"page":"18","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Simple Approach to Dynamic Optimisation of Flexible Optical Networks with Practical Application"],"prefix":"10.3390","volume":"9","author":[{"given":"Vic","family":"Grout","sequence":"first","affiliation":[{"name":"Applied Research in Computing Laboratory (ARCLab), Wrexham Glynd\u0175r University, Wrexham, Wales, LL11 2AW, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,5,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"139","DOI":"10.1023\/A:1024731113866","article-title":"Regenerator Placement and Traffic Engineering with Restoration in GMPLS Networks","volume":"6","author":"Yetginer","year":"2003","journal-title":"Photonic Netw. 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