Module 4 Review Questions

Which of the following are characteristics of ECC?

-Asymmetric encryption -Uses a finite set of values within an algebraic field

Sender and recipient access a reliable counter that computes a new shared value each time a cipher text block is exchanged.

Counter Mode

Which cryptography system generates encryption keys that could be used with DES, AES, IDEA, RC5, or any other symmetric cryptography solution?

Diffie-Hellman

At the end of the cryptographic process, output is generated. With one type of output, simple character changes in the plaintext will cause several characters to change in the cipher text. What type of output is this?

Diffusion

Implements the Diffie-Hellman key exchange protocol using elliptic curve cryptography

ECDH

Mary wants to send a message to Sam. She wants to digitally sign the message to prove that she sent it. Which key would Mary use to create the digital signature?

Mary's private key

Feeds the output blocks back to the block cipher.

Output Feedback Mode

Uses no deterministic algorithm when generating public keys

Perfect forward secrecy

Above all else, what must be protected to maintain the security and benefit of an asymmetric cryptographic solution, especially if it is widely used for digital certificates?

Private keys

Mary wants to send a message to Sam so that only Sam can read it. Which key would be used to encrypt the message?

Sam's public key

A receiver wants to verify the integrity of a message received from a sender. A hashing value is contained within the digital signature of the sender. Which of the following must the receiver use to access the hashing value and verify the integrity of the transmission?

Sender's public key

Can be reused by multiple communication sessions

Static keys

Generates a single key that is used for both encryption and decryption.

Symmetric

If a message sender encrypts a message with a key and a message receiver decrypts it using the same key, which type of key exchange is taking place?

Symmetric

The success of asymmetric encryption is dependent upon which of the following?

The secrecy of the key

How many keys are used with asymmetric (public key) cryptography?

Two

This mode can encrypt or decrypt one fixed-length block.

Block Cipher Mode

Which of the following is used in conjunction with a local security authority to generate the private and public key pair used in asymmetric cryptography?

CSP

Each plaintext block is added to the previous cipher text block and then the result is encrypted with the key.

Cipher Block Chaining Mode

Each cipher text block is fed back into the encryption and then encrypts the next plaintext block.

Cipher Feedback Mode

Algorithm used for signature verification and data integrity checking.

Hashing

Which of the following algorithms are used in asymmetric encryption?

-Diffie-hellman -RSA

You want email sent from users in your organization to be encrypted to make messages more secure. Which of the following is an option you can use to enhance the encryption of email messages?

A cryptographic service provider

Generates two different yet mathematically related keys.

Asymmetric

Only the private key can be used to decrypt information.

Asymmetric

The public key can only be used to encrypt information.

Asymmetric

Which form of asymmetric cryptography is based upon Diffie-Hellman?

El Gamal

Exist only for the lifetime of a specific communication session

Ephemeral keys