Linked Questions

61 votes
3 answers
57k views

Definition of textbook RSA

What is the definition of textbook or "raw" RSA? What are some of the properties of textbook RSA? How does it differ from other schemes based on RSA?
Bobby S's user avatar
  • 1,943
22 votes
1 answer
25k views

What is the maximum size of the plaintext message for RSA OAEP?

OAEP is an important technique used to strengthen RSA. However, using OAEP (or any technique that adds randomness) reduces the size of plaintexts that can be encrypted. Assume for instance that OAEP ...
user avatar
10 votes
3 answers
25k views

Why are RSA ciphertexts different for the same plaintext?

I am using SpongyCastle for a project on android. I have used RSA to encrypt the data and then decrypt it in another activity, the keys are stored in the shared preferences. I discovered a thing I ...
Mayank's user avatar
  • 203
3 votes
2 answers
2k views

Toy public/private key example open to frequency analysis?

I've been looking at an online Public Key Encryption Example (summarized below). It seems to me that choosing cyphertext = plaintext^(key) mod n would produce the ...
Chris Gregg's user avatar
-1 votes
1 answer
9k views

Why plain RSA encryption does not achieve CPA-security?

Why plain RSA encryption does not achieve CPA-security?
node1392's user avatar
3 votes
3 answers
394 views

Is RSA in decline across the board?

From what I gather from the internet (source), the recommended practice for 2019 and beyond is to avoid RSA and use ECDH and ECDSA. Is this the general case?
Bastien's user avatar
  • 511
4 votes
1 answer
931 views

Why does symmetric encryption require padding?

Why does symmetric encryption require padding? Is it to avoid the attacker to learn the size of the plaintext?
신동평's user avatar
3 votes
1 answer
791 views

Appropriate AES key length for short term protection

Currently I'm doing some initial research for a fully connected distributed network communication model. The context here is a peer-to-peer multiplayer protocol, using a majority-voting system. More ...
pauluss86's user avatar
  • 283
1 vote
1 answer
616 views

Is it secure to use RSA to exchange AES key?

I have to create a Client-Server Application using Java and I want to make the communication secure. I thought to use AES to encrypt the messages and for key exchange I make the next steps: Client ...
user99011's user avatar
2 votes
1 answer
128 views

What is the purpose of calculating the N modulus in the encryption phase of asymmetric cryptography?

I was reading a paper entitled : "Mathematical Underpinnings of Asymmetric Cryptography". I came across this If $N$ is the product of two large prime numbers $p$ and $q$, say 300 digits each, and $e$...
Ayadi Ghait's user avatar