Zero-Trust Physical Architecture: The Biometric Corridor
Abstract
"Zero Trust" is a foundational concept in network security—"never trust, always verify." Physical security, however, often relies on a "castle-and-moat" model where a single badge swipe at the perimeter grants unmonitored access to the interior. This paper proposes a "Zero-Trust Physical Architecture" utilizing a sensor-saturated corridor design. By embedding piezoelectric sensors in flooring substrates to track gait and weight continuously, we can achieve "continuous authentication," dynamically reacting to anomalies such as badge swapping or tailgating in real-time.
1. The Fallacy of Static Access Control
Traditional access control systems (ACS) are binary: the door is either locked or unlocked. Once a user passes the checkpoint, the system "trusts" them until the next checkpoint. This leaves a vulnerability window where credentials can be passed to an unauthorized actor, or where a "piggybacker" can slip through.
2. The Biometric Corridor Concept
We propose an architectural intervention: the Biometric Corridor. This is not a checkpoint, but a transit space that continuously verifies identity.
2.1 Piezoelectric Gait Analysis
The floor assembly consists of high-density piezoelectric sensor arrays hidden beneath standard conductive flooring tiles.
- Granularity: Sensors are arranged in a 50mm grid.
- Data Points: The system captures stride length, cadence, foot rotation angle, and dynamic weight distribution (heel-to-toe pressure curve).
- Signature Matching: This unique "gait signature" is compared against the profile associated with the badge used at entry.
2.2 System Logic
If User A scans their badge, the corridor expects User A's gait.
- Entry: Badge Scan. System loads Profile A.
- Transit: Floor sensors track movement.
- Match: Green ambient lighting, door at end unlocks.
- Mismatch (Weight discrepancy > 5% or Gait Deviation): Amber alert. Re-authentication required.
- Tailgating (Two distinct pressure clusters): Red lockdown. Man-trap protocol initiates.
3. Comparison to Network Zero Trust
| Network Zero Trust | Physical Zero Trust |
|---|---|
| Continuous packet inspection | Continuous gait/weight monitoring |
| Behavior analytics (User vs. Baseline) | Movement analytics (Stride vs. Baseline) |
| Micro-segmentation | Dynamic locking of zonal partitions |
4. Implementation Challenges
- False Positives: Injury or footwear changes can alter gait. The system requires a "learning mode" to update user profiles, or a secondary biometric (iris/face) as a fallback.
- Privacy: Biometric data storage must be air-gapped and encrypted, complying with GDPR/CCPA where applicable.
5. Conclusion
The Biometric Corridor transforms architecture from a passive container into an active security agent. It enforces the principle that identity is not a token you hold, but a behavior you exhibit.