How can the secret key be securely shared between Alice and Bob?

How can the secret key be securely shared between Alice and Bob?

Both Alice and Bob share the same secret key. To encrypt the message Alice XORs her message with the shared secret key. To decrypt the message Bob also XORs the message with his (the same) secret key. Exchanging keys with someone must be done in secret.

What key does Alice use to encrypt to Bob?

Bob’s public key
Alice then generates a temporary symmetric key (the pair of orange keys) and uses Bob’s public key (red padlock) to securely send it to Bob. Bob then uses his private key (red key) to unlock his copy of the symmetric key (orange key).

When Bob receives the encrypted message from Alice what key does he use to decrypt the message?

Bob generates two keys, a public key known the the world, and a private key only known to Bob. Alice sends Bob a message and Encrypts it with the Public Key, that is known the world. Bob receives the message and decrypts it with his Private Key which is only known by him. This is the process of asymmetric encryption.

What computations operations do Alice and Bob perform for the cryptographic protection?

To solve this problem, Alice and Bob devised a variety of cryptographic schemes. Before sending a message to Bob, Alice would encrypt it with a secret key, turning plaintext into ciphertext; even if Eve intercepted the ciphertext, she could make no sense of it.

Why is it impossible for Eve to determine the new color mixture she intercepted from Alice and Bob?

How could Alice and Bob agree on a secret color without Eve finding out? Alice and both add their private colors to the other persons mixture and arrive at a shared secret color…. Eve is unable to determine this shared secret color since she needs one of the private colors to do so. And that is the trick.

Which encryption method is most widely used and why?

Public key encryption is fast becoming the most widely used type of encryption because there are no issues to deal with concerning distribution of keys. PGP involves only private key encryption.

When Alice sends a message to Bob encrypted via asymmetric encryption She uses?

Alice uses an asymmetric algorithm to encrypt a message with Bob’s public key and sends him the encrypted data, which he decrypts using the private key. Asymmetric algorithms include a “key generation” protocol that Bob uses to create his key pair, as shown by Figure 15-2.

What is the correct sequence for steps for Alice to send a message to Bob using asymmetric encryption?

Alice wants to sign a message to Bob. She runs her message through a Hashing Algorithm, and then encrypts the resulting digest with her own Private Key. The encrypted digest then gets sent to Bob, along with the original message.

How does Diffie Hellman work?

The Diffie–Hellman (DH) Algorithm is a key-exchange protocol that enables two parties communicating over public channel to establish a mutual secret without it being transmitted over the Internet. DH enables the two to use a public key to encrypt and decrypt their conversation or data using symmetric cryptography.

How are the messages between Bob and Alice encrypted?

If Alice sends Bob a message and that message is encrypted with two keys simultaneously: a symmetric key (Ks) and Bob’s public key. The symmetric key (Ks) is also sent to Bob, encrypted with the private key of Alice.

How is data encrypted in Alice in Wonderland?

To ENCRYPT data, you need only a public key. In this case, Bob has Alice’s public key. He uses this public key to encrypt the data. The data is then sent to Alice. Alice is the only person who can DECRYPT the data, because only she has the private key. The second function is signing. This is not the same as encrypting.

How does Alice and Bob get their keys?

Bob generates a key pair, consisting of his public key (red padlock) and private key (red key). Bob then publishes his public key, and Alice fetches it (Bob mails his padlock to Alice). Alice then generates a temporary symmetric key (the pair of orange keys) and uses Bob’s public key (red padlock) to securely send it to Bob.

How is the symmetric key sent to Bob?

The symmetric key (Ks) is also sent to Bob, encrypted with the private key of Alice. The conclusion reached from this exchange of messages is that Bob can not be sure that the message was written by Alice but Alice can be sure that only Bob can read.