Digital Identity Defense

Tech lead for Amazon Rekognition digital identity at billion-level annual scale.

I am the tech lead for digital identity verification on Amazon Rekognition, defending billion-level annual identity checks against presentation attacks, deepfakes, and injection attacks. The program ships multiple model updates per year to track new threat vectors, and I designed the proactive challenge-response paradigm at its core.

The technical risk that shaped the program: keeping false-positive rates flat for legitimate users while attackers shift from physical spoofs to GenAI deepfakes, a continuous-distribution-shift problem. That problem is what motivated the lifelong-learning research direction. Production constraints become research questions.

Research artifacts: design principles for remote anti-spoofing systems (Xu et al., 2024). Production artifacts include patents on liveness from motion/face/context (Xu et al., 2025), mobile device user authorization (Xu et al., 2025), and gesture/expression/concurrency validation (Zhang et al., 2025), with synthetic-image evaluation of biometric authorization (Xu et al., 2024) as the testing methodology.

References

2025

  1. Patent
    Liveness Detection Based on Motion, Face, and Context Cues
    Xiang Xu, Mingze Xu, Zheng Zhang, and 4 more authors
    2025
    US Patent 12,300,035 B1
  2. Patent
    Mobile Device User Authorization System
    Xiang Xu, Tianchen Zhao, Jon Wu, and 1 more author
    2025
    US Patent 12,418,526 B1
  3. Patent
    Liveness Detection Based on Gesture Validation, Facial Expression Analysis, and Concurrency Validation
    Zheng Zhang, Xiang Xu, Hao Chen, and 2 more authors
    2025
    US Patent 12,333,863

2024

  1. arXiv
    Principles of Designing Robust Remote Face Anti-Spoofing Systems
    Xiang Xu, Tianchen Zhao, Zheng Zhang, and 4 more authors
    arXiv preprint arXiv:2406.03684, 2024
  2. Patent
    Evaluating Biometric Authorization Systems with Synthesized Images
    Xiang Xu, Hao Zhou, Jonathan Wu, and 1 more author
    2024
    US Patent 12,039,027