Security graph construction algorithm based on private set intersection and secret sharing

One or more non-transitory computer-readable storage media encoded with instructions that, when executed by one or more computers, cause the one or more computers to perform operations comprising:

• mapping a first plurality of user identifiers that are active in a first region to generate a first plurality of anonymized user nodes of the first region;
• communicating with one or more devices of a second region, using a privacy set intersection (PSI) protocol, to identify one or more intersecting signals accessed by the first plurality of anonymized user nodes of the first region and a second plurality of anonymized user nodes of the second region;
• constructing a user-signal-user graph based on, at least in part, the one or more intersecting signals and the first plurality of anonymized user nodes of the first region;
• communicating with the one or more devices of the second region, using a secret sharing protocol, to calculate a weight of each intersecting signal, wherein said communicating comprises:
• using the secret sharing protocol to determine a count of anonymized user nodes connected to a particular intersecting signal from the first region and the second region;
• using the secret sharing protocol to determine a count of anonymized user nodes connected to each signal of a different type that neighbors the particular intersecting signal from the first region and the second region;
• and
• calculating the weight of the particular intersecting signal based on the count of anonymized user nodes connected to the particular intersecting signal and the count of anonymized user nodes connected to each signal of a different type that neighbors the particular intersecting signal;
• and
• constructing a use-user graph with at least one edge determined by, at least in part, the weight of each intersecting signal from the user-signal-user graph.

A computer system comprising one or more hardware computer processors configured to perform operations comprising:

• mapping a first plurality of user identifiers that are active in a first region to generate a first plurality of anonymized user nodes of the first region;
• communicating with one or more devices of a second region, using a privacy set intersection (PSI) protocol, to identify one or more intersecting signals accessed by the first plurality of anonymized user nodes of the first region and a second plurality of anonymized user nodes of the second region;
• constructing a user-signal-user graph based on, at least in part, the one or more intersecting signals and the first plurality of anonymized user nodes of the first region;
• communicating with the one or more devices of the second region, using a secret sharing protocol, to calculate a weight of each intersecting signal, wherein said communicating comprises:
• using the secret sharing protocol to determine a count of anonymized user nodes connected to a particular intersecting signal from the first region and the second region;
• using the secret sharing protocol to determine a count of anonymized user nodes connected to each signal of a different type that neighbors the particular intersecting signal from the first region and the second region;
• and
• calculating the weight of the particular intersecting signal based on the count of anonymized user nodes connected to the particular intersecting signal and the count of anonymized user nodes connected to each signal of a different type that neighbors the particular intersecting signal;
• and
• constructing a user-user graph with at least one edge determined by, at least in part, the weight of each intersecting signal from the user-signal-user graph.