{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,20]],"date-time":"2026-03-20T15:50:11Z","timestamp":1774021811949,"version":"3.50.1"},"reference-count":50,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2024,6,28]],"date-time":"2024-06-28T00:00:00Z","timestamp":1719532800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Knowledge Foundation of Sweden","award":["20220072-H-01"],"award-info":[{"award-number":["20220072-H-01"]}]},{"name":"Bavarian State Ministry for Science and Art through the Hightech Agenda (HTA)","award":["20220072-H-01"],"award-info":[{"award-number":["20220072-H-01"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Future Internet"],"abstract":"<jats:p>Multipath wireless access aims to seamlessly aggregate multiple access networks to increase data rates and decrease latency. It is currently being standardized through the ATSSS architectural framework as part of the fifth-generation (5G) cellular networks. However, facilitating efficient multi-access communication in next-generation wireless networks poses several challenges due to the complex interplay between congestion control (CC) and packet scheduling. Given that enhanced ATSSS steering functions for traffic splitting advocate the utilization of multi-access tunnels using congestion-controlled multipath network protocols between user equipment and a proxy, addressing the issue of nested CC becomes imperative. In this paper, we evaluate the impact of such nested congestion control loops on throughput over multi-access tunnels using the recently introduced Multipath DCCP (MP-DCCP) tunneling framework. We evaluate different combinations of endpoint and tunnel CC algorithms, including BBR, BBRv2, CUBIC, and NewReno. Using the Cheapest Path First scheduler, we quantify and analyze the impact of the following on the performance of tunnel-based multipath: (1) the location of the multi-access proxy relative to the user; (2) the bottleneck buffer size, and (3) the choice of the congestion control algorithms. Furthermore, our findings demonstrate the superior performance of BBRv2 as a tunnel CC algorithm.<\/jats:p>","DOI":"10.3390\/fi16070233","type":"journal-article","created":{"date-parts":[[2024,7,1]],"date-time":"2024-07-01T08:17:29Z","timestamp":1719821849000},"page":"233","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Performance Impact of Nested Congestion Control on Transport-Layer Multipath Tunneling"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9017-5071","authenticated-orcid":false,"given":"Marcus","family":"Pieska","sequence":"first","affiliation":[{"name":"Department of Mathematics and Computer Science, Karlstad University, 65188 Karlstad, Sweden"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9446-8143","authenticated-orcid":false,"given":"Andreas","family":"Kassler","sequence":"additional","affiliation":[{"name":"Department of Mathematics and Computer Science, Karlstad University, 65188 Karlstad, Sweden"},{"name":"Intelligent Networks and Systems, Deggendorf Institute of Technology, 94469 Deggendorf, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7311-9334","authenticated-orcid":false,"given":"Anna","family":"Brunstrom","sequence":"additional","affiliation":[{"name":"Department of Mathematics and Computer Science, Karlstad University, 65188 Karlstad, Sweden"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3081-0448","authenticated-orcid":false,"given":"Veselin","family":"Rakocevic","sequence":"additional","affiliation":[{"name":"Department of Engineering, City, University of London, London EC1V 0HB, UK"}]},{"given":"Markus","family":"Amend","sequence":"additional","affiliation":[{"name":"Deutsche Telekom AG, Deutsche-Telekom-Alle 9, 64295 Darmstadt, Germany"}]}],"member":"1968","published-online":{"date-parts":[[2024,6,28]]},"reference":[{"key":"ref_1","unstructured":"Ericsson (2023). 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