Unlock with Your Heart:Heartbeat-based Authentication on Commercial Mobile Phones LEI WANG,State Key Laboratory for Novel Software Technology,Nanjing University,China KANG HUANG,State Key Laboratory for Novel Software Technology,Nanjing University,China KE SUN,State Key Laboratory for Novel Software Technology,Nanjing University,China WEI WANG,State Key Laboratory for Novel Software Technology,Nanjing University,China CHEN TIAN,State Key Laboratory for Novel Software Technology,Nanjing University,China LEI XIE,State Key Laboratory for Novel Software Technology,Nanjing University,China QING GU,State Key Laboratory for Novel Software Technology,Nanjing University,China In this paper,we propose to use the vibration of the chest in response to the heartbeat as a biometric feature to authenticate the user on mobile devices.We use the built-in accelerometer to capture the heartbeat signals on commercial mobile phones. The user only needs to press the phone on his/her chest,and the system can identify the user within a few heartbeats.To reliably extract heartbeat features,we design a two-step alignment scheme that can handle the natural variability in human heart rates.We further use an adaptive template selection scheme to authenticate the user under different body postures and body states.Based on heartbeat signals collected on twenty users,the experimental results show that our method can achieve an authentication accuracy of 96.49%and the heartbeat features are stable over a period of three months. CCS Concepts:.Security and privacy-Biometrics; Additional Key Words and Phrases:Biometrics-based Authentication,Mobile System ACM Reference Format: Lei Wang,Kang Huang.Ke Sun,Wei Wang.Chen Tian,Lei Xie,and Qing Gu.2018.Unlock with Your Heart:Heartbeat- based Authentication on Commercial Mobile Phones.Proc.ACM Interact.Mob.Wearable Ubiquitous Technol.2,3,Article 140 (September 2018),22 pages.https://doiorg/10.1145/3264950 1 INTRODUCTION Biometric features,including fingerprints and faces,have been used as metrics for user authentication on commercial mobile devices.Biometrics-based user authentication systems identify the user based on "who you are",instead of "what you know"(passwords)or "what you have"(tokens)[47].Since users often forget to carry their physical tokens and passwords are susceptible to leakage [5,54],biometrics-based authentication systems Authors'addresses:Lei Wang,State Key Laboratory for Novel Software Technology,Nanjing University,Nanjing,Jiangsu,China,wangl@smail nju.edu.cn:Kang Huang.State Key Laboratory for Novel Software Technology,Nanjing University,Nanjing.Jiangsu,China,hkwany520@ gmail.com;Ke Sun,State Key Laboratory for Novel Software Technology,Nanjing University,Nanjing.Jiangsu,China,kesun@smail.nju.edu.cn Wei Wang.State Key Laboratory for Novel Software Technology,Nanjing University,Nanjing.Jiangsu,China,ww@njuedu.cn;Chen Tian, State Key Laboratory for Novel Software Technology,Nanjing University,Nanjing.Jiangsu,China,tianchen@nju.edu.cn;Lei Xie,State Key Laboratory for Novel Software Technology,Nanjing University,Nanjing,Jiangsu,China,Ixie@nju.edu.cn;Qing Gu,State Key Laboratory for Novel Software Technology,Nanjing University,Nanjing.Jiangsu,China,guq@nju.edu.cn Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page.Copyrights for components of this work owned by others than ACM must be honored.Abstracting with credit is permitted.To copy otherwise,or republish,to post on servers or to redistribute to lists,requires prior specific permission and/or a fee.Request permissions from permissions@acm.org. 2018 Association for Computing Machinery. 2474-9567/2018/9-ART140$15.00 https:/doi.org/10.1145/3264950 Proc.ACM Interact.Mob.Wearable Ubiquitous Technol.,Vol.2,No.3,Article 140.Publication date:September 2018. 140140 Unlock with Your Heart: Heartbeat-based Authentication on Commercial Mobile Phones LEI WANG, State Key Laboratory for Novel Software Technology, Nanjing University, China KANG HUANG, State Key Laboratory for Novel Software Technology, Nanjing University, China KE SUN, State Key Laboratory for Novel Software Technology, Nanjing University, China WEI WANG, State Key Laboratory for Novel Software Technology, Nanjing University, China CHEN TIAN, State Key Laboratory for Novel Software Technology, Nanjing University, China LEI XIE, State Key Laboratory for Novel Software Technology, Nanjing University, China QING GU, State Key Laboratory for Novel Software Technology, Nanjing University, China In this paper, we propose to use the vibration of the chest in response to the heartbeat as a biometric feature to authenticate the user on mobile devices. We use the built-in accelerometer to capture the heartbeat signals on commercial mobile phones. The user only needs to press the phone on his/her chest, and the system can identify the user within a few heartbeats. To reliably extract heartbeat features, we design a two-step alignment scheme that can handle the natural variability in human heart rates. We further use an adaptive template selection scheme to authenticate the user under different body postures and body states. Based on heartbeat signals collected on twenty users, the experimental results show that our method can achieve an authentication accuracy of 96.49% and the heartbeat features are stable over a period of three months. CCS Concepts: • Security and privacy → Biometrics; Additional Key Words and Phrases: Biometrics-based Authentication, Mobile System ACM Reference Format: Lei Wang, Kang Huang, Ke Sun, Wei Wang, Chen Tian, Lei Xie, and Qing Gu. 2018. Unlock with Your Heart: Heartbeat￾based Authentication on Commercial Mobile Phones. Proc. ACM Interact. Mob. Wearable Ubiquitous Technol. 2, 3, Article 140 (September 2018), 22 pages. https://doi.org/10.1145/3264950 1 INTRODUCTION Biometric features, including fingerprints and faces, have been used as metrics for user authentication on commercial mobile devices. Biometrics-based user authentication systems identify the user based on “who you are”, instead of “what you know” (passwords) or “what you have” (tokens) [47]. Since users often forget to carry their physical tokens and passwords are susceptible to leakage [5, 54], biometrics-based authentication systems Authors’ addresses: Lei Wang, State Key Laboratory for Novel Software Technology, Nanjing University, Nanjing, Jiangsu, China, wangl@smail. nju.edu.cn; Kang Huang, State Key Laboratory for Novel Software Technology, Nanjing University, Nanjing, Jiangsu, China, hkwany520@ gmail.com; Ke Sun, State Key Laboratory for Novel Software Technology, Nanjing University, Nanjing, Jiangsu, China, kesun@smail.nju.edu.cn; Wei Wang, State Key Laboratory for Novel Software Technology, Nanjing University, Nanjing, Jiangsu, China, ww@nju.edu.cn; Chen Tian, State Key Laboratory for Novel Software Technology, Nanjing University, Nanjing, Jiangsu, China, tianchen@nju.edu.cn; Lei Xie, State Key Laboratory for Novel Software Technology, Nanjing University, Nanjing, Jiangsu, China, lxie@nju.edu.cn; Qing Gu, State Key Laboratory for Novel Software Technology, Nanjing University, Nanjing, Jiangsu, China, guq@nju.edu.cn. Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. Copyrights for components of this work owned by others than ACM must be honored. Abstracting with credit is permitted. To copy otherwise, or republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. Request permissions from permissions@acm.org. © 2018 Association for Computing Machinery. 2474-9567/2018/9-ART140 $15.00 https://doi.org/10.1145/3264950 Proc. ACM Interact. Mob. Wearable Ubiquitous Technol., Vol. 2, No. 3, Article 140. Publication date: September 2018