A developer is implementing ECDSA for a software signing service. The service signs many documents daily. Which practice is critical to prevent private key recovery?

Using a fixed nonce for all signatures to improve performance

Hashing the message with SHA-1 for faster signing

Generating a new random ephemeral key for each signature

Using a large public key to increase security

A developer is implementing Elgamal signatures. During signing, they compute the signature as (r, s) where r = g^k mod p and s = (H(m) - x*r) * k^(-1) mod (p-1). What is the correct verification equation?

Verify that g^s ≡ y^r * r^H(m) (mod p)

Verify that g^H(m) ≡ y^r * r^s (mod p)

Verify that y^H(m) ≡ g^r * r^s (mod p)

Verify that r^H(m) ≡ g^y * s^r (mod p)

Which of the following correctly pairs an asymmetric algorithm with its underlying security assumption?

DSA – integer factorization; Elgamal – elliptic curve discrete logarithm

RSA – discrete logarithm; ECC – integer factorization

ECC – integer factorization; DSA – elliptic curve discrete logarithm

RSA – integer factorization; ECC – elliptic curve discrete logarithm

EC-CouncilCertified Encryption Specialist

Domain 3Objective 2

RSA, Elliptic Curve, DSA, and Elgamal ECES Practice Questions (Page 3)

Part of the Asymmetric Cryptography and Number Theory domain, which makes up ~17% of our current practice bank. EC-Council does not publish an official question count, but from its 120-minute exam (~50–80 total, ~9–14 in this domain), expect 3–5 from this objective — we provide 43 practice questions to prepare you well beyond it. (estimate)

43questions here

9free pages

11concepts

Questions 11–15

11application · medium
A developer is implementing ECDSA for a software signing service. The service signs many documents daily. Which practice is critical to prevent private key recovery?
Select an answer first
12foundation · easy
In DSA, what are the three public parameters that are shared among users?
Select an answer first
13application · medium
A developer is implementing Elgamal signatures. During signing, they compute the signature as (r, s) where r = g^k mod p and s = (H(m) - x*r) * k^(-1) mod (p-1). What is the correct verification equation?
Select an answer first
14application · medium
A security engineer is testing an RSA implementation. The public key is (n=55, e=7) and the private exponent is d=23. The engineer encrypts the plaintext m=2 using the formula c = m^e mod n. What is the resulting ciphertext?
Select an answer first
15foundation · easy
Which of the following correctly pairs an asymmetric algorithm with its underlying security assumption?
Select an answer first

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RSA, Elliptic Curve, DSA, and Elgamal ECES Practice Questions (Page 3)

Questions 11–15

A developer is implementing ECDSA for a software signing service. The service signs many documents daily. Which practice is critical to prevent private key recovery?

In DSA, what are the three public parameters that are shared among users?

A developer is implementing Elgamal signatures. During signing, they compute the signature as (r, s) where r = g^k mod p and s = (H(m) - x*r) * k^(-1) mod (p-1). What is the correct verification equation?

A security engineer is testing an RSA implementation. The public key is (n=55, e=7) and the private exponent is d=23. The engineer encrypts the plaintext m=2 using the formula c = m^e mod n. What is the resulting ciphertext?

Which of the following correctly pairs an asymmetric algorithm with its underlying security assumption?

Keep studying — Asymmetric Cryptography and Number Theory

A developer is implementing Elgamal signatures. During signing, they compute the signature as (r, s) where r = g^k mod p and s = (H(m) - xr) k^(-1) mod (p-1). What is the correct verification equation?