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Federated Dynamic Graph Neural Networks with Secure Aggregation for Video-based Distributed Surveillance

Published: 03 May 2022 Publication History

Abstract

Distributed surveillance systems have the ability to detect, track, and snapshot objects moving around in a certain space. The systems generate video data from multiple personal devices or street cameras. Intelligent video-analysis models are needed to learn dynamic representation of the objects for detection and tracking. Can we exploit the structural and dynamic information without storing the spatiotemporal video data at a central server that leads to a violation of user privacy? In this work, we introduce Federated Dynamic Graph Neural Network (Feddy), a distributed and secured framework to learn the object representations from graph sequences: (1) It aggregates structural information from nearby objects in the current graph as well as dynamic information from those in the previous graph. It uses a self-supervised loss of predicting the trajectories of objects. (2) It is trained in a federated learning manner. The centrally located server sends the model to user devices. Local models on the respective user devices learn and periodically send their learning to the central server without ever exposing the user’s data to server. (3) Studies showed that the aggregated parameters could be inspected though decrypted when broadcast to clients for model synchronizing, after the server performed a weighted average. We design an appropriate aggregation mechanism of secure aggregation primitives that can protect the security and privacy in federated learning with scalability. Experiments on four video camera datasets as well as simulation demonstrate that Feddy achieves great effectiveness and security.

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      cover image ACM Transactions on Intelligent Systems and Technology
      ACM Transactions on Intelligent Systems and Technology  Volume 13, Issue 4
      August 2022
      364 pages
      ISSN:2157-6904
      EISSN:2157-6912
      DOI:10.1145/3522732
      • Editor:
      • Huan Liu
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      New York, NY, United States

      Publication History

      Published: 03 May 2022
      Online AM: 04 February 2022
      Accepted: 01 November 2021
      Revised: 01 July 2021
      Received: 01 January 2021
      Published in TIST Volume 13, Issue 4

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      Author Tags

      1. Graph neural network
      2. federated learning
      3. secure aggregation
      4. distributed surveillance

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