All Questions
Tagged with symmetric one-time-pad
20
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Can cryptographically secure randomness be used to implement one time pad?
if I use an one time pad key generated using a cryptographically secure random source like python's secret module , to encrypt a message, will the one time pad scheme be secure?
I think the entire ...
3
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2
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141
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Using $key^{th}$ multiple of $\pi$ as a one-time pad
With a key $k$ of sufficient length, say 128 bits, is it possible to use $k^{th}$ multiple of $\pi$ as a one-time pad?
Please enlighten on the security as well as practical aspects (only if secure of ...
- 319
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Are there any known problems performing a One-time pad with 2 keys stored separately - AKA 2 part Symmetric key exchange over TLS
If this is something that already has a name, please tell me to look at that, but I have not been able to find one yet.
I am considering this process for storing some data securely. I want to ...
- 101
1
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1
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145
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Why isn't data encrypted with mutiple ciphers?
Why isn't data encrypted with multiple uncompromised (so far) ciphers? Feel free to answer for a single private key for both and separate private keys.
For example, encrypting data with TwoFish and ...
- 85
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2
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Can a message and one time pad each encrypted with separate ciphers be weaker than the stronger of either cipher?
Assume you have:
A truly random one time pad, $P$
A plain text message, $M$
Two symmetric ciphers, $C_S$ and $C_W$, where $C_S$ is always more secure than $C_W$
Assume the keys have already been ...
- 85
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2
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252
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Two possible plaintext's using OTP decryption
I am using this cipher-text
c = 04 10 12 00 01 08 67 0A 19 65 0F 03 0A 00
with two possible keys
...
- 9
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4
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Why do one-time pads not provide message authentication?
It is often said that one-time pads do not provide message authentication. But, if you and I have a one-time symmetric key, and I send you a message, and it is not complete gibberish, is that itself ...
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372
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Generate one-time-pad with pre-shared key and public randomness
I know very little about cryptography, so I apologize if the question does not make sense.
Let's say we design a function $F(P, X) \rightarrow K$ that takes in a pre-shared private key $P$ and a ...
- 143
1
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1
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288
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How to compare one time pad security and efficiency with AES?
It seems that the minimal size of Pseudorandom permutation (PRP) output is $128$ bits. In general, I'd like to see if there's any minimal size of the output of pseudorandom function (PRF) as well? for ...
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One-time pad question (Old ciphers) [closed]
The plaintext SECRETIVE is encrypted using One Time Pad with key DDDDDDDDD. Which of the following is TRUE?
The ciphertext will be the same as using Caesar cipher with key of 4
The ciphertext is the ...
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2
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139
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How to be sure to retrieve the good key when brute-forcing a cipher?
Imagine the case of the one-time pad. It is proved to be secure because the key could be everything. We have no guarantee that this key or that key was the one used while encrypting our data. ...
4
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4
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703
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Transferring Encrypted One-time pad over the internet
I was working with one-time pad, and as I understand , for one time pad to be 100% secure a key shouldn't be repeated. So assuming Alice and Bob have to exchange messages over the network secured over ...
- 143
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2
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OTP stream cipher
I am new to cryptography, and there is one thing that is bothering me. I hope you can kindly help me to understand.
Let's imagine an attacker harvests the plaintext as well the ciphertext from a ...
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3
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184
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Defining Symmetric vs Asymmetric cryptosystems
I'm writing a project on the advantages and disadvantages of symmetric vs asymmetric cryptosystems. At the moment I am trying to define both systems using mathematical notation. Under the heading "...
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A "one time pad" can be thought of a Vigenere cipher with
A "One Time Pad" can be thought of a Vigenere cipher with...
An infinitely long key
A secure symmetric key
Multiple ciphertext alphabets
A columnar transposition
I had this question come up ...
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