Or the hashes of all the resources loaded by those pages. That collection of prefixes is going to start getting unique quickly. Edit: example: P(baduser | has

Or the hashes of all the resources loaded by those pages. That collection of prefixes is going to start getting unique quickly. Edit: example: P(baduser | hashA )= ~0 P(baduser | hashA and hashB and ... hashF) = 0.75 One prefix doesn't do it, but a bunch together in a smallish time period can fingerprint a site quite well. This is analagous to browser fingerprinting.