User A. Hersean

209

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8

answers

99k

views

How much would it cost in U.S. dollars to brute force a 256 bit key in a year?

brute-force-attack

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127

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90k

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109

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4

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How should I calculate the entropy of a password?

passwords entropy

Jul 10 '20 at 14:17 user81333 1

82

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In end-to-end encryption, doesn't the server need to be trusted?

encryption public-key key-exchange

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52

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2

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12k

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Timing attack and good coding practices

timing-attack

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51

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1

answer

24k

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Easy explanation of "IND-" security notions?

provable-security chosen-plaintext-attack terminology chosen-ciphertext-attack semantic-security

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50

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3

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22k

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Why Curve25519 for encryption but Ed25519 for signatures?

elliptic-curves ed25519 libsodium

Sep 16 '17 at 22:12 Ella Rose 19k

37

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4

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7k

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After 20 years of AES, what are the retrospective changes that should have been made?

aes

Jan 20 at 9:20 Community♦ 1

31

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What are recommended, general strategies to start block-cipher design and/or analysis?

cryptanalysis block-cipher algorithm-design

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30

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6k

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AES-GCM Disadvantage

authenticated-encryption gcm

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28

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1

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13k

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ECDSA, EdDSA and ed25519 relationship / compatibility

elliptic-curves dsa ed25519 eddsa

Feb 13 at 6:39 Patriot 2,933

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1

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Is a hash a zero-knowledge proof?

zero-knowledge-proofs

Jul 4 '19 at 17:05 Geoffroy Couteau 15.5k

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1

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15k

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What are the odds of collisions for a hash function with 256-bit output?

hash collision-resistance

Jun 28 at 14:58 fgrieu♦ 116k

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Why was the winner of the AES competition not a Feistel cipher?

aes substitution-cipher feistel-network

Sep 29 '13 at 20:41 Community♦ 1

18

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3

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UMAC: to what extent is it in use today?

mac

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2

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Elliptic curve ed25519 vs ed448 - Differences

ed25519 ed448

Apr 22 '20 at 13:49 Conrado 5,789

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2

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How safe are Libsodium Crypto Boxes?

libsodium

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3

answers

2k

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How are points on an elliptic curve discretized?

elliptic-curves

Aug 29 '20 at 19:32 fgrieu♦ 116k

11

votes

1

answer

3k

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Security considerations on "expand 32-byte k"-magic number in the Salsa20 family of stream ciphers?

encryption stream-cipher salsa20 constants

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1

answer

3k

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Relation between entropy and min-entropy

entropy

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370

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What role plays Quantum Fourier Transformation in Shor's integer factorization algorithm?

factoring quantum-cryptography

May 3 '19 at 9:28 AleksanderCH 6,207

10

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1

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6k

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Description of signatures with message recovery (as in ISO/IEC 9796-2 and EMV Signatures)

hash signature reference-request message-recovery

May 4 at 15:39 fgrieu♦ 116k

9

votes

1

answer

3k

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Curve25519 over Ed25519 for key exchange? Why?

elliptic-curves key-exchange dsa ed25519

Mar 19 '19 at 16:55 Squeamish Ossifrage 44.1k

9

votes

7

answers

1k

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In search of a pedagogically simple example of asymmetric encryption routine?

public-key algorithm-design pedagogy

Sep 30 '19 at 15:47 postoronnim 129

9

votes

2

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695

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What do NM-CPA and NM-CCA mean?

authenticated-encryption terminology chosen-plaintext-attack chosen-ciphertext-attack malleability

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Why ECDSA has its form?

public-key elliptic-curves signature dsa

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1

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775

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Is forward secrecy overhyped or necessary?

key-generation forward-secrecy

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9

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779

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Soft question: What are examples of beautiful proofs in cryptography? [closed]

history

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GMAC vs HMAC in message forgery and bandwidth

hash tls hmac forgery ghash

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1

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356

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Elliptic Curve Cryptography insecure when input does not lie on the curve?

elliptic-curves

Jun 12 '19 at 3:57 Squeamish Ossifrage 44.1k

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How much would it cost in U.S. dollars to brute force a 256 bit key in a year?

Should we sign-then-encrypt, or encrypt-then-sign?

How should I calculate the entropy of a password?

In end-to-end encryption, doesn't the server need to be trusted?

Timing attack and good coding practices

Easy explanation of "IND-" security notions?

Why Curve25519 for encryption but Ed25519 for signatures?

After 20 years of AES, what are the retrospective changes that should have been made?

What are recommended, general strategies to start block-cipher design and/or analysis?

AES-GCM Disadvantage

ECDSA, EdDSA and ed25519 relationship / compatibility

Is a hash a zero-knowledge proof?

What are the odds of collisions for a hash function with 256-bit output?

Why was the winner of the AES competition not a Feistel cipher?

UMAC: to what extent is it in use today?

Elliptic curve ed25519 vs ed448 - Differences

How safe are Libsodium Crypto Boxes?

How are points on an elliptic curve discretized?

Security considerations on "expand 32-byte k"-magic number in the Salsa20 family of stream ciphers?

Relation between entropy and min-entropy

What role plays Quantum Fourier Transformation in Shor's integer factorization algorithm?

Description of signatures with message recovery (as in ISO/IEC 9796-2 and EMV Signatures)

Curve25519 over Ed25519 for key exchange? Why?

In search of a pedagogically simple example of asymmetric encryption routine?

What do NM-CPA and NM-CCA mean?

Why ECDSA has its form?

Is forward secrecy overhyped or necessary?

Soft question: What are examples of beautiful proofs in cryptography? [closed]

GMAC vs HMAC in message forgery and bandwidth

Elliptic Curve Cryptography insecure when input does not lie on the curve?