CSIA Cybersecurity Exam 2 With Complete Solution

Hiding an object, such as a diary, to prevent others from finding it is an example of: - ANSWER Security through Obscurity An algorithm is a type of: - ANSWER Procedure An encryption algorithm that uses the same ke ...

Hiding an object, such as a diary, to prevent others from finding it is an example of: - ANSWER Security through Obscurity An algorithm is a type of: - ANSWER Procedure An encryption algorithm that uses the same key for both encryption and decryption is: - ANSWER Symmetric The type of cipher that rearranges the test of a message is called: - ANSWER Transposition To use symmetric cryptography, the sender and receiver must share: - ANSWER A secret key The Enigma was: - ANSWER A rotor machine Gilbert Vernam's bit combination operation for encrypting digital teletype transfer is now referred to as: - ANSWER Exclusive or (XOR) TRUE or FALSE The Vigenère cipher uses a series of shifts to encrypt every letter in a message. - ANSWER True TRUE or FALSE The Advanced Encryption Standard (AES) is stronger than the Data Encryption Standard (DES). - ANSWER True TRUE or FALSE Microsoft Windows Professional editions include an encryption feature. - ANSWER True File encryption on the computer's hard drive involves what risk? - ANSWER -Access to low-level data written to the hard drive -Access by a Trojan Horse -Access by a separately booted OS TRUE or FALSE The effort nicknamed DESCHALL used a collection of tens of thousands of computers to crack a DES message by trial and error in 7 months. - ANSWER FALSE it was in 5 months TRUE or FALSE Microsoft's built in encryption protects the user's file against a Trojan Horse. - ANSWER False TRUE or FALSE For encryption to work there must always be a matching decryption algorithm. - ANSWER True The process of decrypting a code is: - ANSWER Cryptanalysis TRUE or FALSE An encryption application program, from a user's point of view, protects a file with a memorized password. - ANSWER True A cryptonet: - ANSWER is two or more people who share an encryption key the following are common ways to handle new encryption keys: - ANSWER -Memorize them -Write them down -Save them to a storage device and download as needed NOT -transfer them via instant messenger An Advanced Encryption Standard (AES) key may not be _____ bits in length A. 16 B. 128 C. 192 D. 256 - ANSWER 16 bits When encrypting a file, a fully punctuated passphrase should have a minimum of ____ characters. - ANSWER 20 Encrypting an encryption key using a passphrase is called: - ANSWER Key wrapping Using the Diffie-Hellman algorithm: - ANSWER both participants in the exchange must have a public/private key pair Digital signatures are often used to provide: - ANSWER Nonrepudiation- Nonrepudiation is the assurance that someone cannot deny something. Typically, nonrepudiation refers to the ability to ensure that a party to a contract or a communication cannot deny the authenticity of their signature on a document or the sending of a message that they originated. To repudiate means to deny. A public-key certificate generally does not contain: - ANSWER a private key To avoid problems with reused encryption keys, you can: - ANSWER combine the key with a nonce TRUE or FALSE After changing an encryption key, all backup copies of the protected file are also protected by the new key. - ANSWER False TRUE or FALSE The shorter the encryption key, the more difficult it is to crack - ANSWER False TRUE or FALSE In cryptography, an internal key exists inside the encryption process and disappears when the process is not running. - ANSWER True TRUE or FALSE When you visit a website with an "https" prefix in the address, the site is secure. - ANSWER True TRUE or FALSE An attacker can modify a file without changing the file's hash value. - ANSWER False TRUE or FALSE A digital signature uses symmetric keys to sign or verify digital data. - ANSWER False TRUE or FALSE A certificate authority is a trusted third party that issues certificates on behalf of some organization - ANSWER True The U.S. government standards published by NIST recommended data with a particular secret key be used for no more than _____ years before changing it. 1,2,3, or 4 years? - ANSWER 2 years Encryption can help protect volumes in the following situations: - ANSWER -When a storage device is lost or stolen -When an eavesdropper looks at the volume without the operating system in place -When discarding a hard drive or other device without wiping it NOT -To prevent physical damage to a hard drive Access Control protects data on a computer against: - ANSWER Hostile users File encryption protects data on a computer against: - ANSWER -Hostile users -Trojans -External files -Lost control -Theft -Recycling Volume encryption protects data on a computer against: - ANSWER -External Files -Lost Control -Theft -Recycling When encrypting data with a block cipher, each repetition is called: - ANSWER a round The following are best practices or proper recommendations for choosing an encryption algorithm: - ANSWER -Use evaluated cryptographic products if using a certified algorithm -Use AES if at all possible -Do not use "private label" algorithms that have not been published and reviewed by the cryptographic community -Check recent news and research results in the crypto community A shortcoming of block ciphers is: - ANSWER encrypting data that has block-sized patterns A self-encrypting drive locks data on the hard disk by: - ANSWER erasing the encryption key when the drive is unplugged or reset The following are properties of persistent key storage: - ANSWER -It uses nonvolatile storage -It can wrap the key using a passphrase -It can store the key on a removable storage device NOT -It uses volatile storage Volume encryption risks include: - ANSWER -Untrustworthy encryption -Encryption integrity -Leaking the plaintext -Data integrity TRUE or FALSE The underlying code of the Rijndael algorithm was leaked to the public in 1994, allowing for successful attacks against data encrypted with Rijndael. - ANSWER False This is the RC4 story with Ron Rivest TRUE or FALSE Changing a single bit of a block cipher's input affects the entire output block. - ANSWER TRUE TRUE or FALSE Cipher block chaining (CBC) is a widely used cipher mode that requires plaintext to be a multiple of the cipher's block size. - ANSWER True TRUE or FALSE A tweakable cipher includes a third input, a nonce-like value that modifies the encryption without the cost of changing the encryption key - ANSWER True Apple Mac OS-X and all editions of Microsoft Windows provide full-disk encryption. - ANSWER False not all editions of windows includes the full-disk encryption There are four strategies for cleaning a hard drive of personal data. Which on will actually make the data un-recoverable? - ANSWER -Run a "disk wipe" program (These are the other 3 strategies) -Delete personal files and "empty the trash" -Reformat the hard drive -Reinstall the operating system TRUE or FALSE A block cipher encrypts data in fixed-sized blocks - ANSWER True AES supports exactly which three key sizes? - ANSWER 128 bits 192 bits 256 bits In the 1970s, the ______ was the only organization in the U.S. government with cryptographic expertise. - ANSWER NSA TRUE or FALSE Ron Rivest developed the RC4 algorithm in the late 1990s. - ANSWER It was the late 1980s