New answers tagged authentication
It is hard to tell exactly what you are asking, but it seems like you are looking for a basic understanding of how authenticator tokens work. See below: https://www.youtube.com/watch?v=k_zpbJF9pmc https://tools.ietf.org/html/rfc6238 https://tools.ietf.org/html/rfc4226
From RFC 4880 - Open PGP Message Format (emphasis added) OpenPGP implementations SHOULD compress the message after applying the signature but before encryption. As the signature provides authentication, and you specifically ask about authentication, I think that quote from the RFC should answer your question. Compression does not affect ...
Authentication can either mean entity authentication or data authentication. Data authentication is a means to demonstrate that some specific data originates from a specific source and has not been modified in transit/on storage. It can be achieved by the use of digital signatures in a public key, i.e., asymmetric, setting or message authentication codes ...
To keep it simple: authentication = something to indicate the origin and authenticity of a document or message. signature = a form of identification in authorizing a document or message. You can authenticate a document/message by “signing” it with a signature, or you can authenticate a document/message by authenticating the document/message itself (using ...
With authentication, only the intended recipient can confirm the authenticity of the message. With signatures, everyone can.
You sign a document with a signature. You authenticate a signature (thus proving the authenticity of the document).
Seems like the answer is that your goal is obviously impossible, without Bob's cooperation. How would Alice distinguish between (1) a write to the disk by Bob's PC, initiated at Bob's request, vs (2) a write to the disk by Bob's PC, initiated by the malware? She can't. They look identical from Alice's perspective. For instance, having Bob's PC sign ...
Yes. $\:$ Since "Eva sees everything written on Bob's PC", the process needs to involve something that's not written on Bob's PC. $\:$ They could use either some sort-of MAC that can be computed with pencil-and paper, or a signature scheme whose private key is held on a hardware token. I don't have any particular such MACs in mind, although my immediate ...
Add to the list FHMQV (probably covered by MQV and HMQV patents), and SM2 (Chinese standard for authenticated key agreement, patented by Chinese government, IPR terms unclear). I personally would probably use FHMQV (permissions/licensing issues aside). It is highly recommended to avoid trying to design your own. If you cannot use any of the existing ...
What about SRP? It has an additional property, that you do not need to keep the shared secret unprotected on the server. http://srp.stanford.edu/design.html You did not specify if you want to restrict the number of roundtrips, but I guess with SRP they can be minimized.
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