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It can’t be because the database does not exist: it is sharded onto each individual phone The server only has a list of random identifiers from those who have
by conradev 6y ago
It can’t be because the database does not exist: it is sharded onto each individual phone
The server only has a list of random identifiers from those who have tested positive for COVID. An exposure notification is determined when a phone downloads that list and correlates it with its local list.
- walterbell 6y ago> when a phone downloads that list After exposure, a time-bounded (?) graph of proximity contact data can join the central list, via the state health app using the local data. This can be cross-referenced with other metadata. Once a human contact tracer establishes communication with the owner of a phone's random identifier, the identifier can be de-anonymized. Even without the new APIs, each phone's location can be collected and shared by telcos, at the granularity of cell tower triangulation.