Page 1583 - (ISC)² CISSP Certified Information Systems Security Professional Official Study Guide

Chapter 7: PKI and Cryptographic

Applications

1. Bob should encrypt the message using Alice’s public key and then
transmit the encrypted message to Alice.

2. Alice should decrypt the message using her private key.

3. Bob should generate a message digest from the plaintext message
using a hash function. He should then encrypt the message digest
using his own private key to create the digital signature. Finally, he
should append the digital signature to the message and transmit it
to Alice.

4. Alice should decrypt the digital signature in Bob’s message using
Bob’s public key. She should then create a message digest from the

plaintext message using the same hashing algorithm Bob used to
create the digital signature. Finally, she should compare the two
message digests. If they are identical, the signature is authentic.