as the public key can be shared with others, anyone can verify the digital signature easily.

Hence, Alice can digitally sign a message using her private key and encrypt the message using the public key of Bob and then sends it to Bob. As no one other than Bob can decrypt and read the message, encryption will provide confidentiality. And, as no one other than Alice can digitally sign the message, the digital signature will prove the authenticity of the message. Also, Alice cannot claim later that she has not sent the message. And, hence, digital signatures also provide non-repudiation.

Some Digital Signature Algorithms

There are many algorithms that can be used to make digital signatures. Some widely used digital signature algorithms are mentioned below:

• RSA (How does RSA cryptosystem work?)
• DSA (How does DSA work?)
• ECDSA
• SHA
• ElGamal Signature Scheme (How does ElGamal encryption work?)

I hope this helps. However, readers who want to know more about how different cryptographic algorithms work and how they are used in various secure network protocols can refer to the book “Cryptography And Public Key Infrastructure.”

Security Fundamentals Practice Tests

The Security Fundamentals Practice Tests test one’s fundamental knowledge of cyber security. The practice tests are good for those who are preparing for various certification exams like the CCNA, CCNP, or CompTIA. They are also good for students and IT/security professionals who want to improve their understanding of cyber security.