Alice and bob encryption example

Alice buys a simple lockbox that closes with a padlock, and puts her message in it. Then she locks it with Bob's padlock, and mails it to Bob. She knows that the mailman can't read the message, as he has no way of opening the padlock. When Bob receives the lockbox he can open it with his key, and read the message.

1. Why are Alice and Bob used for examples?
2. What key does Alice use to encrypt to Bob?
3. Why are Alice and Bob used in cryptography?
4. How confidentiality can be achieved when Alice sends a message to Bob?
5. How can Alice and Bob keep the information they exchange with each other private?
6. Why ticket to Bob is sent to Alice?
7. Who is Alice and Bob Cyber Security Wise?
8. How does Alice guarantee to Bob that it was her who sent the message and that the message wasn t modified during transmission without encrypting the entire message?
9. Which of the following would Alice use to encrypt a message to Bob if she is using asymmetric encryption?
10. What are the 2 main types of cryptographic algorithms?
11. What comes after Alice and Bob?
12. Is Alice an algorithm?
13. What is the problem with Alice sending Bob a message by using her private key to encrypt it while Bob uses Alice's public key to decrypt it?
14. Which type of crypto key can be used to encrypt a message from Alice to Bob where only Bob can be expected to decrypt it?
15. When Alice wants to send confidential email to Bob How do they share a symmetric private key?
16. What should Bob do if he wants to send Alice the digital signature for a message m?
17. What process should bob use if he wants to send a confidential message to Alice using asymmetric cryptography?
18. What does Bob need to know so that he can authenticate Alice?
19. What is the use of a Bob?
20. What is the problem with Alice sending Bob a message by using her private key to encrypt it while Bob uses Alice's public key to decrypt it?
21. What should Bob do if he wants to send Alice the digital signature for a message m?
22. What does Bob mean in relationship?
23. What bob means?
24. Why a bob is used to when diagnosing the network?
25. What is a bob object?
26. How does Alice guarantee to Bob that it was her who sent the message and that the message wasn t modified during transmission without encrypting the entire message?
27. When Bob receives a message from Alice that has been encrypted using asymmetric algorithm which key does he use to decrypt the message?
28. What is an example of public key encryption?
29. How do Bob and Alice the receiver and sender respectively share symmetric keys across a network?
30. What key does Bob use to encrypt the checksum for accomplishing this goal?

Why are Alice and Bob used for examples?

Alice and Bob were the names given to fictitious characters used to explain how the RSA encryption method worked, with the thinking being that using names instead of letters like A and B would make a complex subject easier to grasp.

What key does Alice use to encrypt to Bob?

Alice can pick a secret key K for some symmetric-key cryptosystem, then encrypt K under Bob's public key and send Bob the resulting ciphertext. Bob can decrypt using his private key and recover K . Then Alice and Bob can communicate using a symmetric-key cryptosystem, with K as their shared key, from there on.

Why are Alice and Bob used in cryptography?

Alice and Bob are fictional characters commonly used as placeholders in discussions about cryptographic systems and protocols, and in other science and engineering literature where there are several participants in a thought experiment.

How confidentiality can be achieved when Alice sends a message to Bob?

Only Bob can read this message, since he is the only person who has the secret key that can decrypt her ciphertext message. Thus, using encryption, Alice can ensure that her communication with Bob stays confidential.

How can Alice and Bob keep the information they exchange with each other private?

Alice and Bob each publish a public encryption key, which allows anyone to send them an encrypted message. But they keep secret the corresponding decryption keys, so that only they can read the messages they receive.

Why ticket to Bob is sent to Alice?

Why is the “ticket to Bob” sent by the KDC to Alice—who must then forward it to Bob—instead of being sent directly from the KDC to Bob? This allows Bob to remain stateless. If the “ticket to Bob” was sent directly to Bob, then Bob would have to maintain state while waiting for Alice to contact him.

Who is Alice and Bob Cyber Security Wise?

Alice and Bob are Born

In February 1978, Rivest, Shamir, and Adleman published their paper “A Method for Obtaining Digital Signatures and Public-key Cryptosystems” in Communications of the ACM, (the paper is now typically called the “RSA paper” given its stature in the field).

How does Alice guarantee to Bob that it was her who sent the message and that the message wasn t modified during transmission without encrypting the entire message?

So Alice can use Bob's public key to verify that it was indeed signed by Bob, and then she can decrypt it using her own private key. That way, she knows that (a) Bob sent it and (b) it was sent to her and nobody else read it.

Which of the following would Alice use to encrypt a message to Bob if she is using asymmetric encryption?

Alice can use her own Private Key to encrypt the message. Which makes it so the only key in the world that can decrypt her message is her Public key — which she knows Bob (and anyone else) has access to. The message is sent to Bob, who then uses Alice's Public Key to decrypt the message.

What are the 2 main types of cryptographic algorithms?

Encryption Algorithms

Cryptography is broadly classified into two categories: Symmetric key Cryptography and Asymmetric key Cryptography (popularly known as public key cryptography). Now Symmetric key Cryptography is further categorized as Classical Cryptography and Modern Cryptography.

What comes after Alice and Bob?

Since the late 1970s, cryptographers have been using personal names (instead of labels like “person A” and “person B”) to describe various communications scenarios. Many of these scenarios involve two communicating parties named Alice and Bob and an eavesdropper named Eve.

Is Alice an algorithm?

In this paper, we describe an algorithm called ALICE (Abbreviation LIfter using Corpus-based Extraction). It searches for parentheses and identifies and extracts pairs of abbreviations and their expansions by using heuristic pattern-matching rules. It uses the same strategy used by Yu et al. and Schwartz and Hearst.

What is the problem with Alice sending Bob a message by using her private key to encrypt it while Bob uses Alice's public key to decrypt it?

Alice must've sent it, because only Alice can encrypt something that decrypts properly with Alice's public key.

Which type of crypto key can be used to encrypt a message from Alice to Bob where only Bob can be expected to decrypt it?

Chapter 4: Public-Key Cryptography

Anyone with the public key can encrypt a message but not decrypt it. Only the person with the private key can decrypt the message. Using public-key cryptography, Alice and Bob can communicate securely using the following simple protocol: Alice and Bob agree on a public key algorithm.

When Alice wants to send confidential email to Bob How do they share a symmetric private 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).

What should Bob do if he wants to send Alice the digital signature for a message m?

Bob checks that H(M) = H(M'). If TRUE, then the signature Sig(M) is valid so Bob can be convinced that Alice sent message M' i.e. that M' = M.

What process should bob use if he wants to send a confidential message to Alice using asymmetric cryptography?

If Bob wants to send Alice a secret message, he encrypts it with Alice's public key. Then no one but Alice can decrypt it. Only her private key can undo the encryption, and no one can figure out the private key from the public key.

What does Bob need to know so that he can authenticate Alice?

The use of a nonce is central to public key authentication. If Alice wants to authenticate Bob, she needs to have Bob prove that he possesses his private key (private keys are never shared). To do this, Alice generates a nonce (a random bunch of bits) and sends it to Bob, asking him to encrypt it with his private key.

What is the use of a Bob?

Use in clocks

In most pendulum clocks the rate is adjusted by moving the bob up or down on the pendulum rod. Moving it up shortens the pendulum, making it beat more quickly, and causing the clock to gain time.

What is the problem with Alice sending Bob a message by using her private key to encrypt it while Bob uses Alice's public key to decrypt it?

Alice must've sent it, because only Alice can encrypt something that decrypts properly with Alice's public key.

What should Bob do if he wants to send Alice the digital signature for a message m?

Bob checks that H(M) = H(M'). If TRUE, then the signature Sig(M) is valid so Bob can be convinced that Alice sent message M' i.e. that M' = M.

What does Bob mean in relationship?

Bend Over Boyfriend, slang term for a sexual practice. Berlin Operating Base, the CIA station in Berlin during the Cold War.

What bob means?

a hairstyle that is short at the front while the other hair is cut to neck length all around the head: She wears her hair in a bob.

Why a bob is used to when diagnosing the network?

The BoB improves the quality of A/V signals and is used by many audio/video editors and professional musicians. Another popular use for a BoB is to test and repair technical equipment because it allows a technician to specially test each component and its connection.

What is a bob object?

Any object that hangs on the pendulum string. It can be a toy ball, a bowling ball, or a small car (if the string is string enough). It may be called a "bob" because its vertical position "bobs" up and down while its horizontal motion moves side to side.

How does Alice guarantee to Bob that it was her who sent the message and that the message wasn t modified during transmission without encrypting the entire message?

So Alice can use Bob's public key to verify that it was indeed signed by Bob, and then she can decrypt it using her own private key. That way, she knows that (a) Bob sent it and (b) it was sent to her and nobody else read it.

When Bob receives a message from Alice that has been encrypted using asymmetric algorithm which key does he use to decrypt the message?

When Bob wants to send a message to Alice he uses his copy of her public key to encrypt the message. Alice uses her securely-stored private key to perform the decryption.

What is an example of public key encryption?

Public and private keys: an example

Bob wants to send Alice an encrypted email. To do this, Bob takes Alice's public key and encrypts his message to her. Then, when Alice receives the message, she takes the private key that is known only to her in order to decrypt the message from Bob.

How do Bob and Alice the receiver and sender respectively share symmetric keys across a network?

Both Alice and Bob combine their own ephemeral private key with the other's ephemeral public key (EC point multiplication in the case of ECC), and end up with the same shared secret. This is a point on the elliptic curve, so it will be passed through HKDF, into the correct format and length for the symmetric key.

What key does Bob use to encrypt the checksum for accomplishing this goal?

Explanation. Since Bob has and used Alice's public key to encrypt his message, only Alice's private key can decrypt it.