IP Library Granted Patent US 12,457,110
Granted Patent B2
US 12,457,110 · App. 17/364,048 · Granted Oct 28, 2025

Geospatial-temporal pathogen tracing in zero knowledge

Inventors: Daniel Alan Gregory (Cypress, TX); Prithwish Basu (Lowell, MA); Zachary Ratliff (Somerville, MA); Siddharth Pal (Waltham, MA); Kimberly Gavin (Glen Echo, MD); Benjamin Montgomery (Cambridge, MA); Joud Khoury (Boston, MA)
Assignee: RTX BBN TECHNOLOGIES, INC.
H04L9/3221G06N20/00G16H50/20G16H50/80G16H70/60H04L9/3218H04W4/029
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Quick Facts
Patent No.
US 12,457,110
App. No.
17/364,048
Granted
Oct 28, 2025
Kind
B2
Abstract

Techniques for geospatial-temporal pathogen tracing in zero knowledge include: generating, by a first user device, a first proximity token for contact tracing; receiving, by the first user device, a second proximity token from a second user device; generating, by the first user device, a hash based on the first proximity token and the second proximity token; generating, by the first user device using a prover function of a preprocessing zero knowledge succinct non-interactive argument of knowledge (pp-zk-SNARK), a cryptographic proof attesting that an individual associated with the first user device tested positive for a pathogen; transmitting, by the first user device, first publicly verifiable exposure data including at least the cryptographic proof and the hash to a public registry; and applying at least the first publicly verifiable exposure data and second publicly verifiable exposure data to a machine learning model, to obtain actionable intelligence associated with the pathogen.

Claims (93)

1. One or more non-transitory computer-readable media storing instructions that, when executed by one or more processors, cause the one or more processors to perform operations comprising:

generating, by a first user device, a first proximity token for contact tracing, wherein the first proximity token is generated according to a schedule and based on a random string associated with the first user device;

receiving, by the first user device, a second proximity token from a second user device, wherein the second proximity token is generated according to the schedule and based on a random string associated with the second user device;

sorting, by the first user device, the first proximity token and the second proximity token according to a sorting criteria used by both the first user device and the second user device;

generating, by the first user device, a first hash based on:

the first proximity token and the second proximity token; and

the sorting of the first proximity token and the second proximity token;

generating, by the first user device using a prover function of a preprocessing zero knowledge succinct non-interactive argument of knowledge (pp-zk-SNARK), a first cryptographic proof attesting that:

a first individual associated with the first user device was in a target proximity with a second individual associated with the second user device at a first time point; and

the first individual tested positive for a pathogen at a second time point within a threshold duration of the first time point;

transmitting, by the first user device, first publicly verifiable exposure data comprising at least the first cryptographic proof and the first hash to a public registry;

applying at least the first publicly verifiable exposure data, second publicly verifiable exposure data, and traffic data associated with movement of user devices within a geospatial region to a machine learning model, to obtain actionable intelligence associated with the pathogen;

generating a graph visualization corresponding to the traffic data; and

based at least on the actionable intelligence, determining one or more of:

a predicted future hotspot for the pathogen; and

a pathogen exposure risk of a user of the second user device.

2. The one or more non-transitory computer-readable media of claim 1 , wherein:

generating the first cryptographic proof is based on comparing a first randomness associated with the first hash with a second randomness associated with a second hash comprised in the second publicly verifiable exposure data; and

the machine learning model is a temporal self-attention network.

3. The one or more non-transitory computer-readable media of claim 2 , the operations further comprising:

generating a first regional graph based at least on the first publicly verifiable exposure data;

embedding the first regional graph as a first set of points in a first latent vector space;

generating a second regional graph based at least on the second publicly verifiable exposure data;

embedding the second regional graph as a second set of points in a second latent vector space; and

generating the temporal self-attention network based at least on the first latent vector space and the second latent vector space.

4. The one or more non-transitory computer-readable media of claim 3 , the first regional graph comprising a plurality of nodes representing respective locations in the geospatial region and a plurality of edges representing traffic flow between the respective locations.

5. The one or more non-transitory computer-readable media of claim 1 , the second publicly verifiable exposure data comprising a second cryptographic proof attesting that a second individual associated with the second user device had contact with a third individual associated with a third user device.

6. A system comprising:

at least one device including a hardware processor;

the system being configured to perform operations comprising:

generating, by a first user device, a first proximity token for contact tracing, wherein the first proximity token is generated according to a schedule and based on a random string associated with the first user device;

receiving, by the first user device, a second proximity token from a second user device, wherein the second proximity token is generated according to the schedule and based on a random string associated with the second user device;

sorting, by the first user device, the first proximity token and the second proximity token according to a sorting criteria used by both the first user device and the second user device;

generating, by the first user device, a first hash based on:

the first proximity token and the second proximity token; and

the sorting of the first proximity token and the second proximity token;

generating, by the first user device using a prover function of a preprocessing zero knowledge succinct non-interactive argument of knowledge (pp-zk-SNARK), a first cryptographic proof attesting that:

a first individual associated with the first user device was in a target proximity with a second individual associated with the second user device at a first time point; and

the first individual tested positive for a pathogen at a second time point within a threshold duration of the first time point;

transmitting, by the first user device, first publicly verifiable exposure data comprising at least the first cryptographic proof and the first hash to a public registry;

applying at least the first publicly verifiable exposure data, second publicly verifiable exposure data, and traffic data associated with movement of user devices within a geospatial region to a machine learning model, to obtain actionable intelligence associated with the pathogen;

generating a graph visualization corresponding to the traffic data; and

based at least on the actionable intelligence, determining one or more of:

a predicted future hotspot for the pathogen; and

a pathogen exposure risk of a user of the second user device.

7. The system of claim 6 , wherein:

generating the first cryptographic proof is based on comparing a first randomness associated with the first hash with a second randomness associated with a second hash comprised in the second publicly verifiable exposure data; and

the machine learning model is a temporal self-attention network.

8. The system of claim 7 , the operations further comprising:

generating a first regional graph based at least on the first publicly verifiable exposure data;

embedding the first regional graph as a first set of points in a first latent vector space;

generating a second regional graph based at least on the second publicly verifiable exposure data;

embedding the second regional graph as a second set of points in a second latent vector space; and

generating the temporal self-attention network based at least on the first latent vector space and the second latent vector space.

9. The system of claim 8 , the first regional graph comprising a plurality of nodes representing respective locations in the geospatial region and a plurality of edges representing traffic flow between the respective locations.

10. The system of claim 6 , the second publicly verifiable exposure data comprising a second cryptographic proof attesting that a second individual associated with the second user device had contact with a third individual associated with a third user device.

11. The system of claim 6 , the operations further comprising: generating, by the second user device, a second cryptographic proof attesting that:

the second individual associated with the second user device was in a target proximity with the first individual associated with the first user device at a third time point;

the first individual tested positive for the pathogen; and

the second individual associated with the second user device was in a target proximity with a third individual associated with a third user device at a third time point, wherein the third time point is greater than or equal to a sum of the first time point and an incubation period associated with the pathogen; and

transmitting, by the second user device, second publicly verifiable exposure data comprising at least the second cryptographic proof and a second hash associated with the second user device to the public registry.

12. A method comprising:

generating, by a first user device, a first proximity token for contact tracing, wherein the first proximity token is generated according to a schedule and based on a random string associated with the first user device;

receiving, by the first user device, a second proximity token from a second user device, wherein the second proximity token is generated according to the schedule and based on a random string associated with the second user device;

sorting, by the first user device, the first proximity token and the second proximity token according to a sorting criteria used by both the first user device and the second user device;

generating, by the first user device, a first hash based on:

the first proximity token and the second proximity token; and

the sorting of the first proximity token and the second proximity token;

generating, by the first user device using a prover function of a preprocessing zero knowledge succinct non-interactive argument of knowledge (pp-zk-SNARK), a first cryptographic proof attesting that:

a first individual associated with the first user device was in a target proximity with a second individual associated with the second user device at a first time point; and

the first individual tested positive for a pathogen at a second time point within a threshold duration of the first time point;

transmitting, by the first user device, first publicly verifiable exposure data comprising at least the first cryptographic proof and the first hash to a public registry;

applying at least the first publicly verifiable exposure data, and second publicly verifiable exposure data, and traffic data associated with movement of user devices within a geospatial region to a machine learning model, to obtain actionable intelligence associated with the pathogen;

generating a graph visualization corresponding to the traffic data; and

based at least on the actionable intelligence, determining one or more of:

a predicted future hotspot for the pathogen; and

a pathogen exposure risk of a user of the second user device.

13. The method of claim 12 , wherein:

generating the first cryptographic proof is based on comparing a first randomness associated with the first hash with a second randomness associated with a second hash comprised in the second publicly verifiable exposure data; and

the machine learning model is a temporal self-attention network.

14. The method of claim 13 , further comprising:

generating a first regional graph based at least on the first publicly verifiable exposure data;

embedding the first regional graph as a first set of points in a first latent vector space;

generating a second regional graph based at least on the second publicly verifiable exposure data;

embedding the second regional graph as a second set of points in a second latent vector space; and

generating the temporal self-attention network based at least on the first latent vector space and the second latent vector space.

15. The method of claim 14 , the first regional graph comprising a plurality of nodes representing respective locations in the geospatial region and a plurality of edges representing traffic flow between the respective locations.

16. The method of claim 12 , the second publicly verifiable exposure data comprising a second cryptographic proof attesting that a second individual associated with the second user device had contact with a third individual associated with a third user device.

17. The method of claim 12 , further comprising: generating, by the second user device, a second cryptographic proof attesting that:

the second individual associated with the second user device was in a target proximity with the first individual associated with the first user device at a third time point;

the first individual tested positive for the pathogen; and

the second individual associated with the second user device was in a target proximity with a third individual associated with a third user device at a third time point, wherein the third time point is greater than or equal to a sum of the first time point and an incubation period associated with the pathogen; and

transmitting, by the second user device, second publicly verifiable exposure data comprising at least the second cryptographic proof and a second hash associated with the second user device to the public registry.

Assignments (2)
CHANGE OF NAME Recorded Aug 22, 2024
From: RAYTHEON BBN TECHNOLOGIES CORP.
To: RTX BBN TECHNOLOGIES, INC.
Reel/Frame 068748/0419 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Sep 26, 2022
From: GREGORY, DANIEL ALAN; BASU, PRITHWISH; RATLIFF, ZACHARY; PAL, SIDDHARTH; GAVIN, KIMBERLY; MONTGOMERY, BENJAMIN; KHOURY, JOUD
To: RAYTHEON BBN TECHNOLOGIES CORP.
Reel/Frame 061215/0013 →
Continuity (2)
Provisional Application 63046815 · Jul 1, 2020
Related Publication 20220006635A1 · Jan 6, 2022
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