9
Digital Signatures
In previous chapters, we learned about public-key cryptography and, in particular, public-key cryptography based on elliptic curves. In this chapter, we will take a detailed look at digital signatures, a very important cryptographic mechanism based on public-key cryptography.
We are going to see how sender Alice can generate digital signatures for arbitrary messages and how receiver Bob can verify these signatures, thereby verifying that the messages were not manipulated and were actually sent by Alice.
More precisely, in this chapter, we will cover the following topics:
RSA-based signatures
Signatures based on discrete logarithms
The Digital Signature Algorithm
The Elliptic Curve Digital Signature Algorithm
The digital signature algorithms used in TLS 1.3