NHESS Natural Hazards and Earth System Sciences NHESS Nat. Hazards Earth Syst. Sci. 1684-9981 Copernicus Publications Göttingen, Germany 10.5194/nhess-14-443-2014 Karst show caves – how DTN technology as used in space assists automatic environmental monitoring and tourist protection – experiment in Postojna Cave Gabrovšek F. https://orcid.org/0000-0001-8397-6487 1 Grašič B. 2 Božnar M. Z. 2 Mlakar P. 2 Udén M. 3 Davies E. 4 Karst Research Institute, Research Centre of the Slovenian Academy of Sciences and Arts, Postojna, Slovenia MEIS d.o.o., Mali Vrh pri Šmarju, Slovenia Luleå University of Technology, Luleå, Sweden Folly Consulting Ltd, Cambridgeshire, UK 28 02 2014 14 2 443 457 Copyright: © 2014 F. Gabrovšek et al. 2014 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://nhess.copernicus.org/articles/14/443/2014/nhess-14-443-2014.html The full text article is available as a PDF file from https://nhess.copernicus.org/articles/14/443/2014/nhess-14-443-2014.pdf

The paper presents an experiment demonstrating a novel and successful application of delay- and disruption-tolerant networking (DTN) technology for automatic data transfer in a karst cave early warning and measuring system. The experiment took place inside the Postojna Cave in Slovenia, which is open to tourists. Several automatic meteorological measuring stations are set up inside the cave, as an adjunct to the surveillance infrastructure; the regular data transfer provided by the DTN technology allows the surveillance system to take on the role of an early warning system (EWS). One of the stations is set up alongside the railway tracks, which allows the tourist to travel inside the cave by train. The experiment was carried out by placing a DTN "data mule" (a DTN-enabled computer with WiFi connection) on the train and by upgrading the meteorological station with a DTN-enabled WiFi transmission system. When the data mule is in the wireless drive-by mode, it collects measurement data from the station over a period of several seconds as the train without stopping passes the stationary equipment, and delivers data at the final train station by the cave entrance. This paper describes an overview of the experimental equipment and organization allowing the use of a DTN system for data collection and an EWS inside karst caves where there is regular traffic of tourists and researchers.

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