Linked Questions
49 questions linked to/from How big an RSA key is considered secure today?
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Actual RSA encryption & decryption of strings?
$K_{pub} = (n, e)$
$K_{pvt} = d$
Then
$E_{K_{pub}}(x) \equiv x^e \mod n$
Practically, when RSA is used to encrypt strings, what is the $x$ here? You cannot take it byte by byte because $\mod n$ will ...
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Should RSA primes $p$ and $q$ differ in length by "a few digits"?
When generating RSA keys in the original RSA paper it is stated:
to gain additional protection against sophisticated factoring algorithms, p and q should differ in length by a few digits
Why is ...
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Practical Attack on RSA
Currently I am designing an RSA based application, and I am thinking of how long should the key be in order to be secure against attacks. I know that RSA 4096 bit key can be recovered using Sound ...
CommunityBot
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Historical key sizes for RSA and discrete log [closed]
What is the historical pattern for key size increases for rsa vs discrete log?
What are the current and future projected sizes for these?
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Does the signature length of RS256 depend on the size of the RSA key used for signing?
The following NodeJS code, when run (v16.8.0), logs 512 to stdout.
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Signature of low-entropy data: can they be faked?
I am working on an application where I have a physical product identification label containing a block of public, low-entropy data (~50 bytes) such as serial number and other info, all readily ...
- 141k
2
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1
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How to factorize the group order in Pohlig-Hellman algorithm
The Pohlig-Hellman algorithm is for computing discrete logarithms in a group whose order is a smooth integer.
This algorithm requires the factorization of the group order. However we know that ...
CommunityBot
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1
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Is digital signature without schema possible?
In my application I want to use Rabin crypto system with short keys (like 128 bits) and MD5 for hashing. I found that schema like PKCS1-V1_5 or PPS does not allow you to have such small keys and ...
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Can we sign and encrypt with RSA keys of both sender and receiver?
By using RSA encryption, it is possible to "encrypt" sign with sender's private key and then with receiver's public key, and decrypt with receiver's private key and then with sender's public ...
CommunityBot
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vote
1
answer
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Paillier estimate attack costs on short keys
I was thinking about how to use the homeomorphic property of that cryptosystem to achieve not a "semantic security" but a less ambitous obfuscation of the source code (an ipotetical scenario ...
- 141k
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Prime factorization of 700 decimal digits number
I'm a newbie to encryption. If I create a number 'n' as a product of two prime numbers 'p' and 'q' with the following specifications:
'p' is a fully random prime with 300 decimal digits in length.
'q'...
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Factoring Anderson's RSA backdoor
In 1993, Anderson [1] proposed a backdoor to the RSA key generation algorithm. This backdoor requires that a backdoor key (prime) $A$ be implanted within the key generation portion of the RSA ...
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What is the history of recommended RSA key sizes?
One can find up to date recommended key sizes for RSA at NIST sp800-131A for example. In short, it suggests a key size of at least 2048 bits.
Is it possible to find a history of recommended key sizes ...
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Is an efficient integer factorisation algorithm a threat to security anymore?
Nowadays, private key systems like AES have replaced RSA. Even for digital signatures, people mostly use ECC, so even if an efficient integer factorization algorithm is made, would it be a threat to ...
- 141k
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Should I use RSA encryption since RSA is said to be broken by NSA?
I am developing a simple web app that uses asymmetric encryption, but I am not sure whether to chose RSA for the reasons mentioned above.
What are your suggestions? Also if I decided to go with RSA ...
