{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:08:14Z","timestamp":1760242094437,"version":"build-2065373602"},"reference-count":14,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2018,12,14]],"date-time":"2018-12-14T00:00:00Z","timestamp":1544745600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The media access control (MAC) protocol is a key element in the design of vehicular ad hoc networks (VANETs) that directly affects the network performance. The backoff schemes of existing MAC protocols apply the single backoff process and therefore are not suitable for multi-class data transmission. Additionally, they cannot satisfy the delay requirements of emergency data in the case of varying number of vehicles, causing an adverse effect to the intelligent transportation system (ITS). This paper presents a priority-based adaptive backoff scheme that can enhance the binary exponential backoff (BEB) algorithm as well as the polynomial backoff (QB) algorithm. This system distinguishes priority data with different delay requirements first and designs different backoff schemes for each type of data later. The two-dimensional Markov Chain is used to analyze the backoff scheme and determine the expressions for throughput and delay. The simulation results show that the backoff scheme provided by this paper can reduce the average data delay and regulate each kind of data delay adaptively, according to the varying number of vehicles and different delay requirements.<\/jats:p>","DOI":"10.3390\/s18124421","type":"journal-article","created":{"date-parts":[[2018,12,14]],"date-time":"2018-12-14T04:44:42Z","timestamp":1544762682000},"page":"4421","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["A QoS Based Adaptive Backoff Scheme for Vehicular Ad Hoc Networks"],"prefix":"10.3390","volume":"18","author":[{"given":"Tianjiao","family":"Zhang","sequence":"first","affiliation":[{"name":"Key Lab on Wideband Wireless Communications and Sensor Network Technology of Ministry, Nanjing University of Posts and Telecommunications, Nanjing 210003, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qi","family":"Zhu","sequence":"additional","affiliation":[{"name":"Jiangsu Key Lab of Wireless Communications, Nanjing University of Posts and Telecommunications, Nanjing 210003, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,12,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Mehta, K., Malik, L.L.G., and Bajaj, P. (2013, January 16\u201318). VANET: Challenges, Issues and Solutions. Proceedings of the 2013 6th International Conference on Emerging Trends in Engineering and Technology (ICETET), Nagpur, India.","DOI":"10.1109\/ICETET.2013.18"},{"key":"ref_2","unstructured":"IEEE Std 802.11-2007 (Revision of IEEE Std. 802.11-1999) (2007). Standard for Information Technology-Tele-Communications and Information Exchange between Systems-Local and Metropolitan Area Networks-Specific Requirements Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications, IEEE."},{"key":"ref_3","unstructured":"IEEE Std 802.11p-2010 (2010). Standard for Information Technology-Tele-Communications and Information Exchange between Systems-Local and Metropolitan Area Networks-Specific Requirements Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications Amendment 6: Wireless Access in Vehicular Environments, IEEE."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"14","DOI":"10.1109\/MWC.2006.1593520","article-title":"QoS guarantee and provisioning at the contention-based wireless MAC layer in the IEEE802.11e wireless LANs","volume":"13","author":"Xiao","year":"2006","journal-title":"IEEE Wirel. Commun."},{"key":"ref_5","unstructured":"IEEE Std 802.11-1997 (2018, November 30). Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications [s]. Available online: www.ieee.org."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"535","DOI":"10.1109\/49.840210","article-title":"Performance analysis of the IEEE 802.11 distributed coordination function","volume":"18","author":"Giuseppe","year":"2000","journal-title":"IEEE J. Sel. Areas Commun."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1613","DOI":"10.1109\/TVT.2006.877467","article-title":"A multichain backoff mechanism for IEEE 802.11 WLAN","volume":"55","author":"Ye","year":"2006","journal-title":"IEEE Trans. Veh. Technol."},{"key":"ref_8","first-page":"1","article-title":"Modeling nonsaturated IEEE 802.11 DCF networks utilizing an arbitrary buffer size","volume":"10","author":"Zhao","year":"2010","journal-title":"IEEE Trans. Mob. Comput."},{"key":"ref_9","first-page":"107","article-title":"Backoff algorithm in MAC layer for wireless multimedia sensor networks","volume":"31","author":"Li","year":"2010","journal-title":"J. Commun."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"4182","DOI":"10.1109\/TVT.2013.2275014","article-title":"LIMERIC: A Linear Adaptive Message Rate Algorithm For DSRC Congestion Control","volume":"62","author":"Bansal","year":"2013","journal-title":"IEEE Trans. Veh. Technol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"300","DOI":"10.1109\/TNET.2013.2295242","article-title":"Backoff Design for IEEE 802.11 DCF Networks: Fundamental Tradeoff and Design Criterion","volume":"23","author":"Sun","year":"2015","journal-title":"IEEE\/ACM Trans. Netw."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"5947","DOI":"10.1109\/TWC.2016.2574715","article-title":"Performance Optimization of CSMA Networks With a Finite Retry Limit","volume":"15","author":"Sun","year":"2016","journal-title":"IEEE Trans. Wirel. Commun."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1741","DOI":"10.1109\/TWC.2017.2653113","article-title":"Fairness-Constrained Maximum Sum Rate of Multi-rate CSMA Networks","volume":"16","author":"Sun","year":"2017","journal-title":"IEEE Trans. Wirel. Commun."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1305","DOI":"10.1109\/LCOMM.2017.2681060","article-title":"A Flexible Multi-Channel Coordination MAC Protocol for Vehicular Ad Hoc Networks","volume":"21","author":"Yao","year":"2017","journal-title":"IEEE Commun. Lett."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/18\/12\/4421\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T15:33:54Z","timestamp":1760196834000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/18\/12\/4421"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2018,12,14]]},"references-count":14,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2018,12]]}},"alternative-id":["s18124421"],"URL":"https:\/\/doi.org\/10.3390\/s18124421","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2018,12,14]]}}}