Exam 8: Cryptography

Sequence encryption is a series of encryptions and decryptions between a number of systems, wherein each system in a network decrypts the message sent to it and then reencrypts it using different keys and sends it to the next neighbor. This process continues until the message reaches the final destination.

Within a PKI, a(n)registration authority issues, manages, authenticates, signs, and revokes users' digital certificates, which typically contain the user name, public key, and other identifying information. _________________________

Digital ____________________ are encrypted messages that can be mathematically proven to be authentic.

Describe digital certificates.

A(n) ____________________ substitution uses one alphabet.

A digital ____________________ is an electronic document or container file that contains a key value and identifying information about the entity that controls the key.

The S-HTTP security solution provides six services: authentication by digital signatures, message encryption, compression, e-mail compatibility, segmentation, and key management.

Hashing functions require the use of keys.

The Digital Signature Standard established by NIST is used for electronic document authentication by federal information systems. It is based on a variant of the ElGamal algorithm. _________________________

Bluetooth is a de facto industry standard for short-range wireless communications between devices.

In 1917, Gilbert S. Vernam, an AT&T employee, invented a polyalphabetic cipher machine that used a non-repeating random key.

In a book cipher, the key consists of a list of codes representing the page number, line number, and word number of the plaintext word. _________________________

The process of hiding messages within the digital encoding of a picture or graphic is called ____________________.

Bit stream methods commonly use algorithm functions like the exclusive OR operation (__________).

__________ is a protocol that can be used to secure communications across any IP-based network such as LANs, WANs, and the Internet.

____________________ is the process of making and using codes to secure the transmission of information.

The more common name for asymmetric encryption is ____________________-key encryption.

DES uses a(n) ___________-bit block size.

A cryptovariable is a value representing the application of a hash algorithm on a message.

To perform the Caesar cipher encryption operation, the pad values are added to numeric values that represent the plaintext that needs to be encrypted.