Ch 11-12 Extra Qs

Alice wants to read an encrypted message sent by Bob. Which key is used?

Alice's Private key

Bob receives and encrypted reply message from Alice. Which key is used?

Bo's private key

Bob wants to send Alice a message with a digital signature. Which key is used?

Bob's private key

Bob wants Susan to read Alice's reply message that he received. Which key is used?

Susan's public key

Alice wants to see Bob's digital signature. Which key is used?

Bob's public key

When is a PKI (Public Key Infrastructure) required?

It is necessary to help ascertain the identity of different people, devices, and services. It uses technologies such as digital signatures and digital certificates for credential validation

Bob wants to send a copy to himself of the encrypted message that he sent to Alice. Which key is used?

Bob's public key to encrypt and private key to decrypt

What is the private key used for in asymmetric cryptography?

It is used for decryption

What is the public key used for in asymmetric cryptography?

It is used for encryption

Describe the process of sending a confidential memo:

The sender's message goes through a hash algorithm then a digest. The senders private key uses asymmetric cryptography to generate digital signature. The receiver gets the digital signature and goes through the sender's public key asymmetric cryptography to generate a digest. The digest uses a hash algorithm for finding matches. Once this is done, the receiver is able to read the message.

Bob wants to send Alice an encrypted message. Which key is used?

Alice's Public key

What kind of trust model does PGP (Pretty Good Privacy) use?

It uses Web of Trust Model where participants authenticate the identities of other users