Direct visualization of cryptographic keys for enhanced security


PGP public keys are relatively small binary data. Their hashes are used and also visualized for comparison and validation purposes. We pursue a direct, but previously unused approach. We produce colorful images of public keys and other binary data by generating drawing primitives from binary input. Optionally, we also include the hashes in the visualization. The visualization of raw data together with its hash provides a further security benefit. With it we can visually detect hash collisions. The primary focus of this paper is a direct visualization of public keys. We tune the transparency heuristics for better results. Our method visually detects key spoofing on real SHA1 collision data.

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The author thanks Dr. Andreas Kokott for the discussion of possible online banking improvements with the presented visualization.

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Correspondence to Oleg Lobachev.

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Supplementary material

Supplementary material showing more visualizations is available in the Zenodo repository under

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Lobachev, O. Direct visualization of cryptographic keys for enhanced security. Vis Comput 34, 1749–1759 (2018).

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  • Visualization
  • Cryptography
  • Public key
  • Hash
  • Collision
  • PGP
  • SHA1
  • SHA2