Lecture 5 - Digital Signatures

Question 1

What is a Digital Signature?

Answer 1

Data > Hash > Encrypt hash with signer’s private key > Signature+cert > Attach to data > Digitally signed data

Question 2

List two common digital signature algorithms

Answer 2

1. RSA with MD5
2. DSA with SHA1

Question 3

True or False

Digital signature algorithms do not support non-repudiation.

Answer 3

False

Question 4

List the three parts of a digital signature algorithms

Answer 4

1. Key gen
2. Signature algorithm
3. Verification algorithm

Question 5

Explain what a certificate authority is?

Answer 5

It is a binding between a user and their key

Question 6

Describe PKI

Answer 6

It is the system for issuing and managing certificates.