The hyper-connection of today’s cyber infrastructures enables rapid involution in technology as well as in our society. At the same time, however, the cyberspace and its underlying infrastructure are facing a wide range of risks stemming from both physical and cyber threats and hazards. Every year, industrial leaders and researchers make cyber security predictions for the next year, but often cannot catch up with the new threats. For example, in 2017, the cybersecurity facepalms includes: half a million people’s pacemakers were found vulnerable to being hacked; 143 million American consumers whose sensitive personal information was exposed in the Equifax data breach, and a hacking group called Dragonfly gained direct access to US power grid controls.
Dr. Sun has made pioneering contribution to cybersecurity by introducing the concept of trust into the distributed computing and communication systems, developing theoretical trust models, and designing trust-based solutions to tackle many cyber security challenges.
In 2006, she published a paper entitled “Information theoretic framework of trust modeling and evaluation for ad hoc networks” . This paper presented a new set of theories for trust metrics and trust calculation in computer networks. This work set up the foundation of adopting quantitative and meaningful trust metrics for (a) guiding network entities to detect misbehavior and take actions to avoid risks and (b) stimulating collaboration among distributed network entities. This paper has been cited over 650 times. She advanced the previous theories by adding implementation and security considerations . Her models and theories have been used by many other researchers to develop trust-based security solutions. Her own work on trust-based security solutions has won the best paper award at IEEE SocialCom 2010  (acceptance rate 11%), and the EURASIP 2015 Best Paper Award  (society-wide award, selected from all journals govern by The European Association for Signal Processing, for proven impact and excellence.)
Currently, Dr. Sun’s work on trust modeling focuses on Smart Health, aiming to ensure reliability, security and privacy of healthcare IoT systems.
 Yan Sun, Wei Yu, Zhu Han, and K. J. Ray Liu, “Information Theoretic Framework of Trust Modeling and Evaluation for Ad Hoc Networks”, IEEE Journal on Selected Areas in Communications, vol. 24, no. 2, pp.305- 317, Feb. 2006. (652 citations)
 Yan Sun, Zhu Han, Wei Yu, and K. J. Ray Liu, “A Trust Evaluation Framework in Distributed Networks: Vulnerability Analysis and Defense against Attacks”, in Proc. IEEE INFOCOM’06, Barcelona, April 2006. (339 citations)
 Yan Sun, Zhu Han, and K. J. Ray Liu, “Defense of Trust Management Vulnerabilities in Distributed Networks”, IEEE Communications Magazine, Feature Topic on Security in Mobile Ad Hoc and Sensor Networks, vol. 46, no. 2, pp.112-119, February 2008. (262 citations)
 Yuhong Liu and Yan Lindsay Sun, “Anomaly Detection in Feedback-based Reputation Systems through Temporal and Correlation Analysis”, in Proc. IEEE International Conference on Social Computing (SocialCom2010, acceptance rate 11%), August 2010. (Best Paper Award) (Among over 400 submitted papers, only 2 papers received this award)
 Wenkai Wang, Husheng Li, Yan Sun, and Zhu Han, “Securing Collaborative Spectrum Sensing against Untrustworthy Secondary Users in Cognitive Radio Networks”, EURASIP Journal on Advances in Signal Processing, vol. 2010 (EURASIP 2015 Best Paper Award)