Counter Mode (CTR) is an encryption mode, that builds a random-access stream-cipher from a block-cipher.

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What is the LENGTH parameter in EEA2?

In the EEA2 option for encryption in LTE the AES-128 algorithm is mechanized. There, the nonce used in the CTR Mode is a 128-bit value. The first 64-bits are covered by a COUNTER, a BEARER, a ...
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How does CTR-ESSIV work?

I'm using Wikipedia and Handbook of Applied Cryptography as references. I know that ESSIV generates an initialization vector (IV) by combining a hashed key with the sector number. However, I only see ...
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Pseudorandom Functions with different input and output lengths

I am working on a problem found in my Cryptography textbook that goes as follows: Let F be a pseudorandom function such that for $k \in \{0,1\}^n$, function $F_k$ maps $l_{in}(n)$-inputs to $l_{...
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Authenticating a range of a ciphertext

I have some data that I CTR-AES-256 encrypt already. I am aware of ways to validate the integrity of the entire file (ie: a separate MAC of the plaintext, or encrypt then MAC, etc). But none of ...
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MAC-then-encrypt: Using one-time-MAC with randomized CTR

The Coursera cryptography 1 course says: If you want to use MAC-then-encrypt mode then you should either use randomized-CTR or randomized-CBC. And if you use randomized-CTR then one-time-MAC ...
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Does extra encryption improve the security of CBC and CTR?

I am learning about cryptography and during my research and reading I had a question. When looking at information leakage and CBC mode, I asked if there is a way to improve this with by using the ...
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Message length for aes 256 in ctr, ecb and cbc mode

I want to encrypt a message that have values between 0 and 50. So message have maxim 1 byte. Is possible to encrypt with aes256 in ctr, ecb and cbc mode, messages from 1 byte, not necessary 32 bytes? ...