[irhshafkat]

1. While it's certainly hard to describe all security systems in general, a general rule of thumb is that any system performing similarity matching is going to be considerably more involved than an exact match.

If you want an exact match, like in storing passwords, all you need is to store a hash and throw the original away (and there's certainly more nuances to this, like salting, but the rough idea is this). When a user enters a password, run it through a hash function and see if the hashes match.

This isn't the case for similarity matching, which most face recognition systems use. You need to store the actual embedding, and not the hash, because two face embeddings of even the same person are unlikely to ever be exactly the same, just "close". If you hash even two nearby inputs, any standard hash function will map them as far apart as possible, destroying any sense of distance you'd have to compute the similarity between the stored embedding and the query embedding.

This extends to any method whose internal representations are designed to function based on similarity matches; you need to store the original.

2. Last time I checked, yeah :)