Cryptography

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A ____________is based on information gained from the physical implementation of a cryptosystem, rather than theoretical weaknesses in the algorithms, such as the length of time required during encryption or decryption.

A ____________is based on information gained from the physical implementation of a cryptosystem, rather than theoretical weaknesses in the algorithms, such as the length of time required during encryption or decryption.

__________is a very popular encryption standard created by the NSA. It was one of the first symmetric encryption methods and is now obsolete (known weaknesses can be used to break the encryption). It implements a 64-bit block size with 16 rounds of substitution and transposition.

Data Encryption Standard (DES)

What type of key or keys are used in symmetric cryptography?

A shared private key

Key

Analytic attack

__________________ is an iterative symmetric-key block cipher that was developed as a replacement to DES in 2001. It uses the Rijndael Block Cipher which is resistant to all known attacks. It uses a variable-length block and key length (128-, 192-, or 256-bit keys).

Advanced Encryption Standard (AES)

A _______ is the process or formula used to convert a message or otherwise hide its meaning.

Algorithm

_____________ is the method of recovering original data that has been encrypted without having access to the key used in the encryption process.

Cryptanalysis

A ________is a person who develops ways of converting plain text to cipher text.

Cryptographer

___________ encrypt by transposing plain text to cipher text in chunks and can process large amounts of data.

Block ciphers

A_____________ resides on the client and generates the key pair.

Cryptographic Service Provider (CSP)

_________ is the science of converting data into a secret code to hide the meaning of the message during transmission.

Cryptography

A ____________ is the associated items of cryptography that are used as a unit to provide a single means of encryption and decryption.

Cryptosystem

The ____________is an entity trusted to issue, store, and revoke digital certificates.

Certificate Authority (CA)

The____________ is a declaration of the security that the organization is implementing for all certificates issued by the CA holding the statement. This statement tells potential partners or others relying on the security of the PKI system how well the security of the PKI system is being managed.

Certificate Practice Statement (CPS)

__________is the message in a form that makes it unreadable to all but those for whom the message was intended.

Cipher Text

_________ is the term used to describe a situation in which two different messages produce the same hash value. This is an indication that a stronger hashing algorithm should be used.

Collision

___________ is the procedure used to convert data from cipher text into plain text.

Decryption

A security administrator must implement a system to allow clients to securely negotiate encryption keys with the company's server over a public unencrypted communication channel. Which of the following implements the required secure key negotiation?

Diffie-Hellman

The_____________ was the first asymmetric algorithm. It was developed by Whitfield Diffie and Martin Hellman in 1976. It is a key agreement protocol that generates symmetric keys simultaneously at sender and recipient sites over non-secure channels

Diffie-Hellman Key Exchange

Company A submitted a bid on a contract to do work for Company B via email. Company B was insistent that the bid did not come from Company A. Which of the following would have assured that the bid was submitted by Company A?

Digital signature

________ is the process of using an algorithm to transform data from plain text to a cipher text in order to protect the confidentiality, integrity, and sometimes the authenticity of the message.

Encryption

Joe, a user, wants to send an encrypted email to Ann. Which of the following will Ann need to use to verify the validity's of Joe's certificate?

Joe's public key

A _____ is a variable in a cipher used to encrypt or decrypt a message.

Key

The _______ is the range of the possible values that can be used to construct a key.

Key Space

A message is said to be digitally signed if sent with which of the following?

Message digest encrypted with sender's private key

The ______ is a protocol used for checking the status of an individual digital certificate to verify if it is good or has been revoked.

Online Certificate Status Protocol (OCSP)

In Cryptography, this is the readable message.

Plain text

All of the following are valid cryptographic hash functions EXCEPT:

RC4

When creating a public / private key pair, for which of the following ciphers would a user need to specify the key strength?

RSA

__________is based on factoring large numbers into their prime values.It is one of the most popular and secure asymmetric cryptosystems. It is based on the difficulty of factoring N, a product of two large prime numbers (201 digits).

RSA

A______________ can be used in large, enterprise environments to offload client enrollment request processing by handling verification of clients prior to certificates being issued.

Registration Authority

____ is a variable key-sized block cipher which was designed to replace DES. It was produced by RSA Security, Inc. It uses 64 bit blocks and 8 to 128-bit keys in 8 bit increments. Uses salt, which is used to modify a password hash by using a random string of data to prohibit password hash matching types of attacks.

Ron's Cipher v2 (RC2)

______________, invented around 400 B.C., is an encryption system in which a piece of paper was wrapped around a rod of a specific diameter. The diameter of the rod was the key.

Scytale

Which of the following encrypts data a single bit at a time?

Stream Cipher

____________use a sequence of bits known as a keystream, which is the key used for encryption. They are best used for small amounts of data, usually less than 64 bits.

Stream ciphers

The___________ is responsible for issuing certificates, holding the CPS, and publishing the CRL. Subordinate CAs function within the hierarchy in a parent-child relationship with the root CA.

Subordinate CA

____________ (also known as secret-key encryption, pre-shared key, or private-key encryption) uses only one key to encrypt and decrypt data.

Symmetric-key encryption

How many keys are used in Asymmetric encryption?

Two

What is the official standard of ITU Telecommunication Standardization Sector (ITU-T) that identifies the format for public key certificates and certification path validation.

X.509

An_____________ uses an algebraic manipulation to reduce the complexity of the algorithm.

analytic attack

A __________ in which the attacker produces cipher text and then sends it through a decryption process to see the resulting plain text.

chosen cipher text attack

A _________ is an electronic document that uses a digital signature to bind together a public key with an identity. Identity information includes the name of a person, computer, or organization.

digital certificate

A _______ is a function that takes a variable-length string (message) and compresses and transforms it into a fixed-length value.

hash

An __________ is a seed value used in encryption. The seed value and the key are used in an encryption algorithm to generate additional keys or to encrypt data.

initialization vector (IV)

A __________ is a cryptography method in which the plain text is converted to binary and combined with a string of randomly generated binary numbers. It is a form of substitution.

one-time pad

A __________ replaces one set of characters with symbols or another character set.

substitution cipher

A _________ (also called an anagram) changes the position of characters in the plain text message.

transposition cipher


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