Appendix to SoK: Continuous Authentication Beyond Error Rates: Reviewing General System Properties

System	Use case	Resource to be secured	Attacker model	Deployment scheme, location of enrollment	Deployment scheme, location of authentication	Algorithmic approach	Privacy measures Entries marked with * are considered to be misconceptions	System response after failed authentication	Re-authentication strategie
Mahfouz, A., Hamdy, A., Eldin, M. A., & Mahmoud, T. M. (2024). B2auth: A contextual fine-grained behavioral biometric authentication framework for real-world deployment. Pervasive and Mobile Computing, 101888. https://doi.org/10.1016/j.pmcj.2024.101888	General smartphone	Client device	Access to client and compromised credentials	Server	Client	Classification
Li, Y., Huang, Y., & Huang, H. (2024). FuMeAuth: Sensor-Based Continuous Authentication Using Fused Memory-Augmented Transformer Autoencoder. IEEE Internet of Things Journal, 1–1. https://doi.org/10.1109/JIOT.2024.3394437	General smartphone	Client device	Access to client and compromised credentials	Server	Client	Anomaly detection		Lock the device
Li, Y., Liu, L., Deng, S., Qin, H., El-Yacoubi, M. A., & Zhou, G. (2024). Memory-Augmented Autoencoder Based Continuous Authentication on Smartphones With Conditional Transformer GANs. IEEE Transactions on Mobile Computing, 23(5), 4467–4482. https://doi.org/10.1109/TMC.2023.3290834	General smartphone	Client device	Access to client	Server	Client	Anomaly detection		Lock the device	Explicit Authentication
Alawami, M. A., Abuhmed, T., Abuhamad, M., & Kim, H. (2024). MotionID: Towards practical behavioral biometrics-based implicit user authentication on smartphones. Pervasive and Mobile Computing, 101, 101922. https://doi.org/10.1016/j.pmcj.2024.101922	General smartphone	Client device	Access to client	Server	Server	Anomaly detection		Lock the device
Li, Y., Ouyang, C., & Huang, H. (2024). AEGANAuth: Autoencoder GAN-Based Continuous Authentication With Conditional Variational Autoencoder Generative Adversarial Network. IEEE Internet of Things Journal, 11(16), 27635–27650. IEEE Internet of Things Journal. https://doi.org/10.1109/JIOT.2024.3399549	General mobile devices	Client device	Access to client and compromised credentials	Server	Client	Anomaly detection		Lock the device	Explicit Authentication
Lopez, J. M. E., Celdran, A. H., Esquembre, F., Perez, G. M., & Marin-Blazquez, J. G. (2023). CGAPP: A continuous group authentication privacy-preserving platform for industrial scene. JOURNAL OF INFORMATION SECURITY AND APPLICATIONS, 78, 103622. https://doi.org/10.1016/j.jisa.2023.103622	Smartphone app in enterprise environment	Client App	Unspecified	Client / Server	Client	Classification	Discussed but not implemented	Lock the device, report to the management, undo the last action
Fereidooni, H., Koenig, J., Rieger, P., Chilese, M., Goekbakan, B., Finke, M., Dmitrienko, A., & Sadeghi, A.-R. (2023). AuthentiSense: A Scalable Behavioral Biometrics Authentication Scheme using Few-Shot Learning for Mobile Platforms. Proceedings 2023 Network and Distributed System Security Symposium. Network and Distributed System Security Symposium, San Diego, CA, USA. https://doi.org/10.14722/ndss.2023.23194	General smartphone apps	Cloud resource	Access to client	Server	Server	Classification			Explicit Authentication
Yang, H., Meng, X., Zhao, X., Wang, Y., Liu, Y., Kang, X., Shen, J., & Huang, W. (2023). CKDAN: Content and keystroke dual attention networks with pre-trained models for continuous authentication. In COMPUTERS & SECURITY (Vol. 128). ELSEVIER ADVANCED TECHNOLOGY. https://doi.org/10.1016/j.cose.2023.103159	Computer in in enterprise environment	Client device	Access to client	Server	Server	Anomaly detection		Lock the device, disconnect the network, shutdown the device	Explicit Authentication, help from administrator
Huh, J. H., Kwag, S., Kim, I., Popov, A., Park, Y., Cho, G., Lee, J., Kim, H., & Lee, C.-H. (2023). On the Long-Term Effects of Continuous Keystroke Authentication: Keeping User Frustration Low through Behavior Adaptation. In PROCEEDINGS OF THE ACM ON INTERACTIVE MOBILE WEARABLE AND UBIQUITOUS TECHNOLOGIES-IMWUT (Vol. 7, Issue 2). ASSOC COMPUTING MACHINERY. https://doi.org/10.1145/3596236	General smartphone	Client device	Access to client and compromised credentials	Client	Client	Classification	Local processing	Lock the device
Zhang, J., Li, Z., Zhang, H., Zhang, W., Ling, Z., & Yang, M. (2023). Sensor-based implicit authentication through learning user physiological and behavioral characteristics. Computer Communications, 208, 244–255. https://doi.org/10.1016/j.comcom.2023.06.016	General smartphone	Client device	Access to client	Client	Client	Anomaly detection	Local processing	Lock the device	Explicit Authentication
Gan, W., Chen, X., Wang, W., Chen, L., Wu, J., Wang, X., He, X., & Wu, F. (2022). Multi-device Continuous Authentication Mechanism Based on Homomorphic Encryption and SVM Algorithm. In X. Sun, X. Zhang, Z. Xia, & E. Bertino (Eds.), Artificial Intelligence and Security (pp. 625–638). Springer International Publishing. https://doi.org/10.1007/978-3-031-06791-4_49	General mobile devices and computer	Client device	Unspecified	Server	Server	Classification	Homomorphic encryption	temporary block the client, restrict permissions, block the client	Timeout
Sahu, A. K., Sharma, S., & Raja, R. (2022). Deep Learning-based Continuous Authentication for an IoT-enabled healthcare service. Computers and Electrical Engineering, 99, 107817. https://doi.org/10.1016/j.compeleceng.2022.107817	Mobile devices in enterprise environment	Client device	Access to client and compromised credentials	Server	Server	Classification	Keeping biometric data in enterprise networks*		Reassess the authentication of the user
Stylios, I., Skalkos, A., Kokolakis, S., & Karyda, M. (2022). BioPrivacy: A behavioral biometrics continuous authentication system based on keystroke dynamics and touch gestures. INFORMATION AND COMPUTER SECURITY, 30(5), 687–704. https://doi.org/10.1108/ICS-12-2021-0212	General smartphone	Client device	Access to client and compromised credentials	Server	Server	Classification
Stylios, I., Skalkos, A., Kokolakis, S., & Karyda, M. (2022). BioPrivacy: A behavioral biometrics continuous authentication system based on keystroke dynamics and touch gestures. INFORMATION AND COMPUTER SECURITY, 30(5), 687–704. https://doi.org/10.1108/ICS-12-2021-0212	Smartphone app in enterprise environment	Client App	Unspecified	Server	Server	Anomaly Detection / Classification
Gupta, S., Kumar, R., Kacimi, M., & Crispo, B. (2022). IDeAuth: A novel behavioral biometric-based implicit deauthentication scheme for smartphones. Pattern Recognition Letters, 157, 8–15. https://doi.org/10.1016/j.patrec.2022.03.011	General smartphone apps	Client App	Access to client	Client	Client	Anomaly detection	Local processing	Sign-off the applications on the smartphone
Monschein, D., Peregrina Perez, J. A., Piotrowski, T., Nochta, Z., Waldhorst, O. P., & Zirpins, C. (2021). Towards a Peer-to-Peer Federated Machine Learning Environment for Continuous Authentication. 2021 IEEE Symposium on Computers and Communications (ISCC), 1–6. https://doi.org/10.1109/ISCC53001.2021.9631491	Cryptocurrency exchange plattforms	Cloud resource	Compromised credentials	Server	Server	Classification	Format preserving encryption
Monschein, D., & Waldhorst, O. P. (2021). SPCAuth: Scalable and Privacy-Preserving Continuous Authentication for Web Applications. 2021 IEEE 46th Conference on Local Computer Networks (LCN), 281–286. https://doi.org/10.1109/LCN52139.2021.9524959	General cloud service	Cloud resource	Compromised credentials	Server	Server	Classification	Discussed but not implemented	Backend denies actions or requests additional confirmations
Monschein, D., & Waldhorst, O. P. (2021). SPCAuth: Scalable and Privacy-Preserving Continuous Authentication for Web Applications. 2021 IEEE 46th Conference on Local Computer Networks (LCN), 281–286. https://doi.org/10.1109/LCN52139.2021.9524959	General cloud service	Cloud resource	Unspecified	Server	Server	Classification
Hernández-Álvarez, L., de Fuentes, J. M., González-Manzano, L., & Hernández Encinas, L. (2021). SmartCAMPP - Smartphone-based continuous authentication leveraging motion sensors with privacy preservation. Pattern Recognition Letters, 147, 189–196. https://doi.org/10.1016/j.patrec.2021.04.013	General smartphone	Client device	Access to client	Server	Server	Classification	Format preserving encryption
Espín López, J. M., Huertas Celdrán, A., Marín-Blázquez, J. G., Esquembre, F., & Martínez Pérez, G. (2021). S3: An AI-Enabled User Continuous Authentication for Smartphones Based on Sensors, Statistics and Speaker Information. Sensors, 21(11), Article 11. https://doi.org/10.3390/s21113765	General smartphone	Client App	Unspecified	Server	Server	Anomaly detection	Discussed but not implemented
Labayen, M., Vea, R., Flórez, J., Aginako, N., & Sierra, B. (2021). Online Student Authentication and Proctoring System Based on Multimodal Biometrics Technology. IEEE Access, 9, 72398–72411. IEEE Access. https://doi.org/10.1109/ACCESS.2021.3079375	E-Learning plattforms	Cloud resource	Impersonation attack	Server	Server	Anomaly detection / Classification	Anonymize biometric data*
Cola, G., Vecchio, A., & Avvenuti, M. (2021). Continuous authentication through gait analysis on a wrist-worn device. Pervasive and Mobile Computing, 78, 101483. https://doi.org/10.1016/j.pmcj.2021.101483	Smartwatch	Client device	Access to client	Client	Client	Anomaly detection	Local processing
Sanchez, P. M. S., Maimo, L. F., Celdran, A. H., & Perez, G. M. (2021). AuthCODE: A privacy-preserving and multi-device continuous authentication architecture based on machine and deep learning. COMPUTERS & SECURITY, 103, 102168. https://doi.org/10.1016/j.cose.2020.102168	Computer in in enterprise environment	Client device	Unspecified	Server	Server	Classification	Aggregation of features over time*	Lock the device	Explicit Authentication
Acar, A., Aksu, H., Uluagac, A. S., & Akkaya, K. (2021). A Usable and Robust Continuous Authentication Framework Using Wearables. IEEE Transactions on Mobile Computing, 20(6), 2140–2153. https://doi.org/10.1109/TMC.2020.2974941	Computer in in enterprise environment	Client device	Compromised credentials	Server	Server	Anomaly detection & Classification	Transmit features, not raw data*	Locke the device, alert management and security teams, notify user via e-mail	Explicit Authentication
Acar, A., Aksu, H., Uluagac, A. S., & Akkaya, K. (2021). A Usable and Robust Continuous Authentication Framework Using Wearables. IEEE Transactions on Mobile Computing, 20(6), 2140–2153. https://doi.org/10.1109/TMC.2020.2974941	General computer	Client device	Access to client	Server	Server	Anomaly detection	Noise tolerant template security	Lock the device	Explicit Authentication
Acar, A., Ali, S., Karabina, K., Kaygusuz, C., Aksu, H., Akkaya, K., & Uluagac, S. (2021). A Lightweight Privacy-Aware Continuous Authentication Protocol-PACA. ACM Transactions on Privacy and Security, 24(4), 24:1-24:28. https://doi.org/10.1145/3464690	Virtual Desktops	Cloud resource	Compromised credentials	Server	Server	Classification		Lock the deivce, log an alarm, notify the user via e-mail or text message	Explicit Authentication
Rocha, R., Carneiro, D., & Novais, P. (2021). Continuous authentication with a focus on explainability. In NEUROCOMPUTING (Vol. 423, pp. 697–702). ELSEVIER. https://doi.org/10.1016/j.neucom.2020.02.122	General smartphone	Client device	Access to client and compromised credentials	Server	Server	Classificaion		Lock the device	Explicit Authentication
Buriro, A., Gupta, S., Yautsiukhin, A., & Crispo, B. (2021). Risk-Driven Behavioral Biometric-based One-Shot-cum-Continuous User Authentication Scheme. In JOURNAL OF SIGNAL PROCESSING SYSTEMS FOR SIGNAL IMAGE AND VIDEO TECHNOLOGY (Vol. 93, Issue 9, pp. 989–1006). SPRINGER. https://doi.org/10.1007/s11265-021-01654-2	General smartphone apps	Client App	Access to client and compromised credentials	Server	Server	Classification	Discussed but not implemented	Block activities	Propt for re-authentication
Barlas, Y., Basar, O. E., Akan, Y., Isbilen, M., Alptekin, G. I., & Incel, O. D. (2020). DAKOTA: Continuous Authentication with Behavioral Biometrics in a Mobile Banking Application. 2020 5th International Conference on Computer Science and Engineering (UBMK), 1–6. https://doi.org/10.1109/UBMK50275.2020.9219365	Online Banking	Client App	Unspecified	Server	Server	Anomaly detection
Kašys, K., Dundulis, A., Vasiljevas, M., Maskeliūnas, R., & Damaševičius, R. (2020). BodyLock: Human Identity Recogniser App from Walking Activity Data. In O. Gervasi, B. Murgante, S. Misra, C. Garau, I. Blečić, D. Taniar, B. O. Apduhan, A. M. A. C. Rocha, E. Tarantino, C. M. Torre, & Y. Karaca (Eds.), Computational Science and Its Applications – ICCSA 2020 (pp. 307–319). Springer International Publishing. https://doi.org/10.1007/978-3-030-58802-1_23	General smartphone	Client device	Access to client	Server	Server	Classification		Block access to data, inform the owner about the location of the device
Xu, W., Shen, Y., Luo, C., Li, J., Li, W., & Zomaya, A. Y. (2020). Gait-Watch: A Gait-based context-aware authentication system for smart watch via sparse coding. Ad Hoc Networks, 107, 102218. https://doi.org/10.1016/j.adhoc.2020.102218	Smartwatch	Client device	Access to client and compromised credentials	Client	Client	Anomaly detection
Shrestha, P., & Saxena, N. (2020). Hacksaw: Biometric-free non-stop web authentication in an emerging world of wearables. Proceedings of the 13th ACM Conference on Security and Privacy in Wireless and Mobile Networks, 13–24. https://doi.org/10.1145/3395351.3399366	General cloud service	Cloud resource	Compromised credentials	Server	Server	Classification	Not use privacy sensitive biometrics*	Restrict access, alert the user, de-authenticate the session
Liang, X., Zou, F., Li, L., & Yi, P. (2020). Mobile terminal identity authentication system based on behavioral characteristics. International Journal of Distributed Sensor Networks, 16(1), 1550147719899371. https://doi.org/10.1177/1550147719899371	General smartphone apps	Client App	Access to client	Server	Server	Classification	Not use privacy sensitive biometrics*	Lock the device	Explicit Authentication
Zhu, T., Qu, Z., Xu, H., Zhang, J., Shao, Z., Chen, Y., Prabhakar, S., & Yang, J. (2020). RiskCog: Unobtrusive Real-Time User Authentication on Mobile Devices in the Wild. IEEE Transactions on Mobile Computing, 19(2), 466–483. IEEE Transactions on Mobile Computing. https://doi.org/10.1109/TMC.2019.2892440	General mobile devices	Client device	Access to client and compromised credentials	Server	Server/Client	Classification	Discussed but not implemented
Sánchez Sánchez, P. M., Huertas Celdrán, A., Fernández Maimó, L., Martínez Pérez, G., & Wang, G. (2019). Securing Smart Offices Through an Intelligent and Multi-device Continuous Authentication System. In G. Wang, A. El Saddik, X. Lai, G. Martinez Perez, & K.-K. R. Choo (Eds.), Smart City and Informatization (pp. 73–85). Springer. https://doi.org/10.1007/978-981-15-1301-5_7	Computer in in enterprise environment	Client device	Unspecified	Server	Server	Classification	Aggregation of features over time*	Lock the device
Mainali, P., Shepherd, C., & Petitcolas, F. A. P. (2019). Privacy-Enhancing Context Authentication from Location-Sensitive Data. Proceedings of the 14th International Conference on Availability, Reliability and Security, 1–10. https://doi.org/10.1145/3339252.3340334	General cloud service	Cloud resource	Unspecified	Server	Server	Anomaly detection	Hashing biometric data
Li, Q., & Chen, H. (2019). CDAS: A Continuous Dynamic Authentication System. Proceedings of the 2019 8th International Conference on Software and Computer Applications, 447–452. https://doi.org/10.1145/3316615.3316691	General smartphone	Client device	Unspecified	Server	Client	Classification		Issue a warning
Mostafa, H., El-Ramly, M., Elkorany, A. M., & Shaban, H. (2019). Behavio2Auth: Sensor-based Behavior Biometric Authentication for Smartphones. Proceedings of the ArabWIC 6th Annual International Conference Research Track, 1–6. https://doi.org/10.1145/3333165.3333176	General smartphone	Client device	Access to client	Client	Client	Anomaly detection	Local processing	Lock the device	Explicit Authentication
Hintze, D., Füller, M., Scholz, S., Findling, R. D., Muaaz, M., Kapfer, P., Koch, E., & Mayrhofer, R. (2019). CORMORANT: Ubiquitous Risk-Aware Multi-Modal Biometric Authentication across Mobile Devices. Proceedings of the ACM on Interactive, Mobile, Wearable and Ubiquitous Technologies, 3(3), 85:1-85:23. https://doi.org/10.1145/3351243	General mobile devices	Client device	Access to client	Unkown	Unkown	Unknown		Lock the device	Explicit Authentication
Wu, C., He, K., Chen, J., & Du, R. (2019). ICAuth: Implicit and Continuous Authentication When the Screen Is Awake. ICC 2019 - 2019 IEEE International Conference on Communications (ICC), 1–6. https://doi.org/10.1109/ICC.2019.8761435	General smartphone	Client device	Access to client and compromised credentials	Server	Client	Classification			-
Pang, X., Yang, L., Liu, M., & Ma, J. (2019). MineAuth: Mining Behavioural Habits for Continuous Authentication on a Smartphone. In J. Jang-Jaccard & F. Guo (Eds.), Information Security and Privacy (pp. 533–551). Springer International Publishing. https://doi.org/10.1007/978-3-030-21548-4_29	General smartphone	Client device	Access to client	Client	Client	Anomaly detection	Local processing	Lock the device	Explicit Authentication
Jorquera Valero, J. M., Sanchez Sanchez, P. M., Fernandez Maimo, L., Huertas Celdran, A., Arjona Fernandez, M., De Los Santos Vilchez, S., & Martinez Perez, G. (2018). Improving the Security and QoE in Mobile Devices through an Intelligent and Adaptive Continuous Authentication System. SENSORS, 18(11), 3769. https://doi.org/10.3390/s18113769	Mobile banking app	Client device	Unspecified	Client	Client	Anomaly detection	Local processing	Block the app, block sensitive data and transactions, allow limited payments only
Fenu, G., & Marras, M. (2018). Controlling User Access to Cloud-Connected Mobile Applications by Means of Biometrics. IEEE Cloud Computing, 5(4), 47–57. https://doi.org/10.1109/MCC.2018.043221014	General cloud service	Cloud resource	Unspecified	Server	Server	Anomaly detection		Sign-off the session
Fenu, G., Marras, M., & Boratto, L. (2018). A multi-biometric system for continuous student authentication in e-learning platforms. Pattern Recognition Letters, 113, 83–92. https://doi.org/10.1016/j.patrec.2017.03.027	E-Learning plattforms	Cloud resource	Impersonation attack	Server	Server	Anomaly detection
Shila, D. M., & Srivastava, K. (2018). CASTRA: Seamless and Unobtrusive Authentication of Users to Diverse Mobile Services. IEEE Internet of Things Journal, 5(5), 4042–4057. https://doi.org/10.1109/JIOT.2018.2851501	General smartphone apps	Client App	Access to client	Server	Server	Anomaly detection	Using a random identifier*	Lock access to sensitive services	Active authentication foctur such as fingerprint, voice or faice
Shepherd, C., Akram, R. N., & Markantonakis, K. (2017). Towards trusted execution of multi-modal continuous authentication schemes. Proceedings of the Symposium on Applied Computing, 1444–1451. https://doi.org/10.1145/3019612.3019652	General computer	Client device	Access to client and compromised credentials (sholder surfing)	Client	Client	Classification	Local processing
Centeno, M. P., Moorsel, A. V., & Castruccio, S. (2017). Smartphone Continuous Authentication Using Deep Learning Autoencoders. 2017 15th Annual Conference on Privacy, Security and Trust (PST), 147–1478. https://doi.org/10.1109/PST.2017.00026	General smartphone	Client device	Unspecified	Server	Server	Anomaly detection
Lee, W.-H., & Lee, R. B. (2017). Implicit Smartphone User Authentication with Sensors and Contextual Machine Learning (arXiv:1708.09754). arXiv. http://arxiv.org/abs/1708.09754	General smartphone	Client App	Access to client	Server	Client	Classification	Anonymize biometric data*	Lock the device	Explicit authentication, possibly with biometrics
Schiavone, E., Ceccarelli, A., & Bondavalli, A. (2017). Continuous Biometric Verification for Non-Repudiation of Remote Services. Proceedings of the 12th International Conference on Availability, Reliability and Security, 1–10. https://doi.org/10.1145/3098954.3098969	General cloud service	Cloud resource	Access to client	Server	Server	Unknown
Traoré, I., Nakkabi, Y., Saad, S., Sayed, B., Ardigo, J. D., & de Faria Quinan, P. M. (2017). Ensuring Online Exam Integrity Through Continuous Biometric Authentication. In I. Traoré, A. Awad, & I. Woungang (Eds.), Information Security Practices: Emerging Threats and Perspectives (pp. 73–81). Springer International Publishing. https://doi.org/10.1007/978-3-319-48947-6_6	E-Learning plattforms	Cloud resource	Impersonation attack	Server	Server	Anomaly detection
Lee, W.-H., & Lee, R. B. (2017). Implicit Smartphone User Authentication with Sensors and Contextual Machine Learning. 297–308. https://doi.org/10.1109/DSN.2017.24	General smartphone apps	Client App	Access to client	Server	Client	Classification	Anonymize biometric data*	Lock the device, refuse access to security-critical data	Explicit Authentication
Li, Q., Wang, L., Kim, T., & Im, E. G. (2016). Mobile-based continuous user authentication system for cloud security. 2016 IEEE International Conference on Network Infrastructure and Digital Content (IC-NIDC), 176–179. https://doi.org/10.1109/ICNIDC.2016.7974559	General cloud service	Cloud resource	Compromised credentials	Server	Server	Classification		Deny access to remote ressources
Shahandashti, S. F., Safavi-Naini, R., & Safa, N. A. (2015). Reconciling user privacy and implicit authentication for mobile devices. Computers & Security, 53, 215–233. https://doi.org/10.1016/j.cose.2015.05.009	General cloud service	Cloud resource	Access to client	Server	Server	Anomaly detection	Homomorphic encryption	Log out the user	Explicit Authentication
Crouse, D., Han, H., Chandra, D., Barbello, B., & Jain, A. K. (2015). Continuous authentication of mobile user: Fusion of face image and inertial Measurement Unit data. 2015 International Conference on Biometrics (ICB), 135–142. https://doi.org/10.1109/ICB.2015.7139043	General smartphone	Client device	Access to client	Server	Server	Classification		Log out the user
Feng, T., Yang, J., Yan, Z., Tapia, E. M., & Shi, W. (2014). TIPS: Context-aware implicit user identification using touch screen in uncontrolled environments. Proceedings of the 15th Workshop on Mobile Computing Systems and Applications, 1–6. https://doi.org/10.1145/2565585.2565592	General smartphone apps	Client App	Unspecified	Client	Client	Anomaly detection	Local processing	Block access to application	Explicit Authentication
Khan, H., Atwater, A., & Hengartner, U. (2014). Itus: An implicit authentication framework for android. Proceedings of the 20th Annual International Conference on Mobile Computing and Networking, 507–518. https://doi.org/10.1145/2639108.2639141	General smartphone apps	Client App	Access to client	Client	Client	Unknown		Lock the application	Explicit Authentication with seperate credentials
Li, L., Zhao, X., & Xue, G. (2013). Unobservable Re-authentication for Smartphones. Network and Distributed System Security Symposium. https://www.semanticscholar.org/paper/Unobservable-Re-authentication-for-Smartphones-Li-Zhao/e86dd9e5ed2033cf7eab97245912b6d21c4c78a3	General smartphone	Client device	Access to client	Client / Server	Client	Classification	Anonymize biometric data*	Lock the device, send message with location of the device to the user's e-mail	Administrator password
Crawford, H., Renaud, K., & Storer, T. (2013). A framework for continuous, transparent mobile device authentication. In COMPUTERS & SECURITY (Vol. 39, Issue B, pp. 127–136). ELSEVIER ADVANCED TECHNOLOGY. https://doi.org/10.1016/j.cose.2013.05.005	General smartphone apps	Client App	Access to client and compromised credentials	Client	Client	Classification	Local processing	Deny a desired task	Explicit Authentication
Feng, T., Zhao, X., Carbunar, B., & Shi, W. (2013). Continuous Mobile Authentication Using Virtual Key Typing Biometrics. 2013 12th IEEE International Conference on Trust, Security and Privacy in Computing and Communications, 1547–1552. https://doi.org/10.1109/TrustCom.2013.272	General smartphone	Client device	Access to client and compromised credentials	Client	Client	Unknown	Local processing	Lock out the user
Shi, W., Yang, J., Jiang, Y., Yang, F., & Xiong, Y. (2011). SenGuard: Passive user identification on smartphones using multiple sensors. 2011 IEEE 7th International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob), 141–148. https://doi.org/10.1109/WiMOB.2011.6085412	General smartphone	Client device	Access to client	Client	Client	Classification		Lock the device	Explicit Authentication
Chow, R., Jakobsson, M., Masuoka, R., Molina, J., Niu, Y., Shi, E., & Song, Z. (2010). Authentication in the clouds: A framework and its application to mobile users. Proceedings of the 2010 ACM Workshop on Cloud Computing Security Workshop, 1–6. https://doi.org/10.1145/1866835.1866837	General smartphone apps	Cloud resource	Access to client and compromised credentials	Server	Server	Anomaly detection	Hashing of features	Reject a user request
Niinuma, K., Park, U., & Jain, A. K. (2010). Soft Biometric Traits for Continuous User Authentication. In IEEE TRANSACTIONS ON INFORMATION FORENSICS AND SECURITY (Vol. 5, Issue 4, pp. 771–780). IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC. https://doi.org/10.1109/TIFS.2010.2075927	General computer	Client device	Access to client and compromised credentials	Client	Client	Anomaly detection	Local processing	Lockt the device	Time decay, hard and soft biometrics