Chapter 8 - Info & Network Security

What size key does a DES system use?

56 bit

Which of the following is an operation used on binary numbers not found in normal math?

AND

A(n) ___________is a set of steps for doing something.

Algorithm

Which of the following is most likely to be true of an encryption method advertised as unbreakable?

It is likely to be exaggerated.

Many classic ciphers are easy to understand, but not secure. What is the main problem with simple substitution?

It maintains letter and word frequency

A(n) ________ refers to the bits that are combined with the plain text to encrypt it.

Key

With asymmetric cryptography a different ______ is used to encrypt the message and to decrypt the message.

Key

____ key is used to encrypt a message, and another is used to decrypt the message.

Public key

Which of the following is most true regarding binary operations and encryption?

They can form a part of viable encryption methods.

Which of the following methods uses a variable-length symmetric key?

Blowfish

_________ is a block cipher that uses a variable-length key ranging from 32 to 448 bits.

Blowfish

Using the __________ cipher you choose some number by which to shift each letter of a text.

Caesar

Which of the following is a symmetric key system using 64-bit blocks?

DES

______________ is the process to scramble a message or other information so that it cannot be easily read.

Encryption

What should you be most careful of when looking for an encryption method to use?

How long the algorithm has been around

Why is binary mathematical encryption not secure?

It does not change letter or word frequency

What advantage does a symmetric key system using 64-bit blocks have?

It is fast

Classic ciphers were improved with multiple shifts (multiple substitution alphabets). Which of the following is an encryption method using two or more different shifts?

Multi-alphabet encryption

Using the _________ cipher you select multiple numbers by which to shift letters.

Multi-alphabet substitution

Which of the following is most true regarding new encryption methods?

Never use them until they have been proven.

Which of the following methods is available as an add-in for most email clients?

PGP

What is PGP?

Pretty Good Privacy, a public key encryption method

What type of encryption uses different keys to encrypt and decrypt the message?

Public key

Which of the following is most true regarding certified encryption methods?

There is no such thing as certified encryption.

Which of these is NOT a type of symmetric algorithm? a. Block b. Ceasar c. Transcription d. Stream

Transcription

Which of these is NOT a type of symmetric algorithm????

Transcription (REPEAT OF 31)

A digital signature is used to guarantee who sent a message. This is referred to as non-repudiation.

True

A virtual private network is a way to use the Internet to create a connection between a remote user and a central location.

True

Binary numbers are made up of 0s and 1s.

True

Cipher text is encrypted text.

True

Kerberos is an authentication protocol that uses a ticket granting system that sends an encrypted ticket to the user's machine.

True

L2TP uses IPsec for its encryption.

True

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.

True

The most widely used symmetric key algorithm is Advanced Encryption Standard.

True

Which binary mathematical operation can be used for a simple (but unsecured) encryption method and is in fact a part of modern symmetric ciphers?

XOR

________ refers to unencrypted text.

plain text

Which of the following is the oldest encryption method discussed in this text?

Caesar cipher

It is important to understand the concepts and application of cryptography. Which of the following most accurately defines encryption?

Changing a message so it can only be easily read by the intended recipient.

__________refers to encrypted text. a. Plain text b. Key c. Cipher text d. Algorithm

Cipher text

__________ is the art to write in or decipher secret code.

Cryptography

IPsec can only encrypt the packet data but not the header information.

False

PGP involves only private key encryption.

False

Windows stores passwords using a method called __________.

Hashing