Design of cryptographic protocols, i.e. ways of using algorithms (primitives) to achieve one or more security goals like integrity, confidentiality, authenticity (maybe together with non-security-related goals). If you ask about a specific protocol, tag with its name instead (or additionally, if ...
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How can I encrypt more than 64 bit with the Data Encryption Standard?
The Data Encryption Algorithm is designed to encipher and decipher blocks of data consisting of 64 bits under control of a 56-bit key.
If my data is more than 64 bits, (suppose 66 or 67 bits), will ...
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Changing algorithms during encryption
Inspired by "Guarding against cryptanalytic breakthroughs: combining multiple hash functions", I am curious if there is a cryptographic reason to use only one algorithm during encryption.
For ...
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Generating non-repeating N-bit IVs, which are indistinguishable from randomness
I'm implementing a protocol which needs a 64-bit IV for every encrypted packet. The cipher in use (AES-GCM, more or less as specified in RFC 4106) does not require that these IVs are random, only ...
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Why choose an authenticated encryption mode instead of a separate MAC?
What are cryptographic reasons to choose an authenticated-encryption mode of operation (such as GCM) over a traditional encryption mode plus an independent MAC, or vice versa?
Assume there is no ...
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1answer
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How to collect, process, and transmit data securely?
In my question "Authenticating data generated by a particular build of an open source program", Dave Cary requested that I post a question stating my real problem on a high level rather than the ...
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Authenticating data generated by a particular build of an open source program
[I was torn between posting here or security.stackexchange.com. In the end, I felt that this was more of a design question, rather than an implementation question and so chose this forum.]
My ...
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Is using slow password hashing on the client side easier attackable than on the server side?
As we know, one should use a slow password hashing algorithm instead of a fast one for storing passwords, to hinder brute force attacks when the database is compromised. The problem with this is that ...
