{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,17]],"date-time":"2026-06-17T05:13:36Z","timestamp":1781673216910,"version":"3.54.5"},"reference-count":34,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2023,4,30]],"date-time":"2023-04-30T00:00:00Z","timestamp":1682812800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"The CAS &amp; Bengbu Technology Transfer Project","award":["ZKBB202102"],"award-info":[{"award-number":["ZKBB202102"]}]},{"name":"The CAS &amp; Bengbu Technology Transfer Project","award":["2021021"],"award-info":[{"award-number":["2021021"]}]},{"name":"The CAS &amp; Bengbu Technology Transfer Project","award":["YZJJ2022QN02"],"award-info":[{"award-number":["YZJJ2022QN02"]}]},{"name":"The CAS &amp; Bengbu Technology Transfer Project","award":["2022ZA03"],"award-info":[{"award-number":["2022ZA03"]}]},{"name":"Hefei Municipal Natural Science Foundation","award":["ZKBB202102"],"award-info":[{"award-number":["ZKBB202102"]}]},{"name":"Hefei Municipal Natural Science Foundation","award":["2021021"],"award-info":[{"award-number":["2021021"]}]},{"name":"Hefei Municipal Natural Science Foundation","award":["YZJJ2022QN02"],"award-info":[{"award-number":["YZJJ2022QN02"]}]},{"name":"Hefei Municipal Natural Science Foundation","award":["2022ZA03"],"award-info":[{"award-number":["2022ZA03"]}]},{"name":"Hefei Institutes of Physics Science, Chinese Academy Sciences","award":["ZKBB202102"],"award-info":[{"award-number":["ZKBB202102"]}]},{"name":"Hefei Institutes of Physics Science, Chinese Academy Sciences","award":["2021021"],"award-info":[{"award-number":["2021021"]}]},{"name":"Hefei Institutes of Physics Science, Chinese Academy Sciences","award":["YZJJ2022QN02"],"award-info":[{"award-number":["YZJJ2022QN02"]}]},{"name":"Hefei Institutes of Physics Science, Chinese Academy Sciences","award":["2022ZA03"],"award-info":[{"award-number":["2022ZA03"]}]},{"name":"Guangdong Provincial Key Laboratory of Intelligent Disaster Prevention and Emergency Technologies for Urban Lifeline Engineering","award":["ZKBB202102"],"award-info":[{"award-number":["ZKBB202102"]}]},{"name":"Guangdong Provincial Key Laboratory of Intelligent Disaster Prevention and Emergency Technologies for Urban Lifeline Engineering","award":["2021021"],"award-info":[{"award-number":["2021021"]}]},{"name":"Guangdong Provincial Key Laboratory of Intelligent Disaster Prevention and Emergency Technologies for Urban Lifeline Engineering","award":["YZJJ2022QN02"],"award-info":[{"award-number":["YZJJ2022QN02"]}]},{"name":"Guangdong Provincial Key Laboratory of Intelligent Disaster Prevention and Emergency Technologies for Urban Lifeline Engineering","award":["2022ZA03"],"award-info":[{"award-number":["2022ZA03"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In 2016, Google proposed a congestion control algorithm based on bottleneck bandwidth and round-trip propagation time (BBR). The BBR congestion control algorithm measures the network bottleneck bandwidth and minimum delay in real-time to calculate the bandwidth delay product (BDP) and then adjusts the transmission rate to maximize throughput and minimize latency. However, relevant research reveals that BBR still has issues such as RTT unfairness, high packet loss rate, and deep buffer performance degradation. This article focuses on its most prominent RTT fairness issue as a starting point for optimization research. Using fluid models to describe the data transmission process in BBR congestion control, a fairness optimization strategy based on pacing gain is proposed. Triangular functions, inverse proportional functions, and gamma correction functions are analyzed and selected to construct the pacing gain model, forming three different adjustment functions for adaptive adjustment of the transmission rate. Simulation and real experiments show that the three optimization algorithms significantly improve the fairness and network transmission performance of the original BBR algorithm. In particular, the optimization algorithm that employs the gamma correction function as the gain model exhibits the best stability.<\/jats:p>","DOI":"10.3390\/s23094431","type":"journal-article","created":{"date-parts":[[2023,5,1]],"date-time":"2023-05-01T12:12:11Z","timestamp":1682943131000},"page":"4431","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Optimization of BBR Congestion Control Algorithm Based on Pacing Gain Model"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5092-4231","authenticated-orcid":false,"given":"Shuang","family":"Yang","sequence":"first","affiliation":[{"name":"Anhui Provincial Key Laboratory of Photonic Devices and Materials, Anhui Institute of Optics and Fine Mechanics, HFIPS, Chinese Academy of Sciences, Hefei 230031, China"},{"name":"University of Science and Technology of China, Hefei 230026, China"},{"name":"Guangdong Provincial Key Laboratory of Intelligent Disaster Prevention and Emergency Technologies for Urban Lifeline Engineering, Dongguan 523808, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuquan","family":"Tang","sequence":"additional","affiliation":[{"name":"Anhui Provincial Key Laboratory of Photonic Devices and Materials, Anhui Institute of Optics and Fine Mechanics, HFIPS, Chinese Academy of Sciences, Hefei 230031, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0640-9299","authenticated-orcid":false,"given":"Wansu","family":"Pan","sequence":"additional","affiliation":[{"name":"Anhui Provincial Key Laboratory of Photonic Devices and Materials, Anhui Institute of Optics and Fine Mechanics, HFIPS, Chinese Academy of Sciences, Hefei 230031, China"},{"name":"University of Science and Technology of China, Hefei 230026, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Huadong","family":"Wang","sequence":"additional","affiliation":[{"name":"Anhui Provincial Key Laboratory of Photonic Devices and Materials, Anhui Institute of Optics and Fine Mechanics, HFIPS, Chinese Academy of Sciences, Hefei 230031, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dandan","family":"Rong","sequence":"additional","affiliation":[{"name":"Anhui Provincial Key Laboratory of Photonic Devices and Materials, Anhui Institute of Optics and Fine Mechanics, HFIPS, Chinese Academy of Sciences, Hefei 230031, China"},{"name":"University of Science and Technology of China, Hefei 230026, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhirong","family":"Zhang","sequence":"additional","affiliation":[{"name":"Anhui Provincial Key Laboratory of Photonic Devices and Materials, Anhui Institute of Optics and Fine Mechanics, HFIPS, Chinese Academy of Sciences, Hefei 230031, China"},{"name":"University of Science and Technology of China, Hefei 230026, China"},{"name":"Guangdong Provincial Key Laboratory of Intelligent Disaster Prevention and Emergency Technologies for Urban Lifeline Engineering, Dongguan 523808, China"},{"name":"Advanced Laser Technology Laboratory of Anhui Province, Hefei 230037, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,4,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1145\/1024908.1024910","article-title":"Congestion control in IP\/TCP internetworks","volume":"14","author":"Nagle","year":"1984","journal-title":"ACM SIGCOMM Comput. 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