{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,12]],"date-time":"2026-05-12T08:20:52Z","timestamp":1778574052876,"version":"3.51.4"},"reference-count":57,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2021,7,5]],"date-time":"2021-07-05T00:00:00Z","timestamp":1625443200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Electronics"],"abstract":"<jats:p>The increase of data-rates that are provided by free-space optical (FSO) communications is essential in our data-driven society. When used in satellite and interplanetary networks, these optical links can ensure fast connections, yet they are susceptible to atmospheric disruptions and long orbital delays. The Delay and Disruption Tolerant Networking (DTN) architecture ensures a reliable connection between two end nodes, without the need for a direct connection. This can be an asset when used with FSO links, providing protocols that can handle the intermittent nature of the connection. This paper provides a review on the theoretical and state-of-the-art studies on FSO and DTN. The aim of this review is to provide motivation for the research of an optical wireless satellite network, with focus on the use of the Licklider Transmission Protocol. The assessment presented establishes the viability of these networks, providing many examples to rely on, and summarizing the most recent stage of the development of the technologies addressed.<\/jats:p>","DOI":"10.3390\/electronics10131607","type":"journal-article","created":{"date-parts":[[2021,7,5]],"date-time":"2021-07-05T22:02:04Z","timestamp":1625522524000},"page":"1607","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Review on Free-Space Optical Communications for Delay and Disruption Tolerant Networks"],"prefix":"10.3390","volume":"10","author":[{"given":"Mafalda","family":"Goncalves Teixeira","sequence":"first","affiliation":[{"name":"Institute for Communications and Navigation, Deutsches Zentrum f\u00fcr Luft- und Raumfahrt (DLR), M\u00fcnchener Str. 20, 82234 We\u00dfling, Germany"}]},{"given":"Julio Ramirez","family":"Molina","sequence":"additional","affiliation":[{"name":"Institute for Communications and Navigation, Deutsches Zentrum f\u00fcr Luft- und Raumfahrt (DLR), M\u00fcnchener Str. 20, 82234 We\u00dfling, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8057-5474","authenticated-orcid":false,"given":"Vasco N. G. J.","family":"Soares","sequence":"additional","affiliation":[{"name":"Polytechnic Institute of Castelo Branco, 6000-084 Castelo Branco, Portugal"},{"name":"Instituto de Telecomunica\u00e7\u00f5es, 6201-001 Covilh\u00e3, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,7,5]]},"reference":[{"key":"ref_1","unstructured":"Mahdy, A., and Deogun, J.S. (2004, January 21\u201325). Wireless optical communications: A survey. Proceedings of the 2004 IEEE Wireless Communications and Networking Conference (IEEE Cat. No.04TH8733), Atlanta, GA, USA."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"72","DOI":"10.1109\/35.735881","article-title":"Optical wireless: The story so far","volume":"36","author":"Heatley","year":"1998","journal-title":"IEEE Commun. Mag."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Da Silva, A.P., Burleigh, S., and Obraczka, K. (2018). 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