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pre assessment introduction to cryptography
wgu d334<\/p>\n\n\n\n
DES
64 Bit Block – 56 Bit Key – 16 Rounds<\/p>\n\n\n\n
AES
128 Bit Block – 128, 192, 256 Bit Key – 10, 12, 14 Rounds<\/p>\n\n\n\n
BlowFish
64 Bit Block – 32 thru 448 Bit Key – 16 Rounds<\/p>\n\n\n\n
TwoFish
128 Bit Block – 1 thru 256 Bit Key – 16 Rounds<\/p>\n\n\n\n
Serpent
128 Bit Block 128, 192, 256 Bit Key – 32 Rounds<\/p>\n\n\n\n
SkipJack
64 Bit Block – 80 Bit Key – 32 Rounds<\/p>\n\n\n\n
IDEA
64 Bit Block – 128 Bit Key – 8.5 Rounds<\/p>\n\n\n\n
Symmetric Block Ciphers
DES – AES – BlowFish – TwoFish – Serpent – SkipJack – IDEA<\/p>\n\n\n\n
Symmetric Block Ciphers with 64 Bit Block Size
DES – BlowFish – SkipJack – IDEA<\/p>\n\n\n\n
Symmetric Block Ciphers with 128 Bit Block Size
AES – TwoFish – Serpent<\/p>\n\n\n\n
Symmetric Block Ciphers with 128, 192, 256 Bit Key Size
AES – Serpent<\/p>\n\n\n\n
Symmetric Block Ciphers with 16 Rounds
DES – BlowFish – TwoFish<\/p>\n\n\n\n
Symmetric Block Ciphers with 32 Rounds
Serpent – SkipJack<\/p>\n\n\n\n
RC4
1 thru 2048 Bit Key Size & 1 Round (40 bit minimum recommended)<\/p>\n\n\n\n
FISH
Uses Lagged Fibonacci pseudorandom number generator<\/p>\n\n\n\n
PIKE
Revised version of FISH to address known plaintext attack vulnerabilities<\/p>\n\n\n\n
Symmetric Stream Ciphers
RC4 – Fish – Pike<\/p>\n\n\n\n
Asymmetric Encryption Algos
RSA – ECC – El Gamal – DSA<\/p>\n\n\n\n
RSA
Leverages prime number characteristics, 1024-4096 bit variable key size, 1 round. Uses Trapdoor function to enable use for encryption and digital signatures. One-way trapdoor functions can be inverted with knowledge of trapdoor factorization information.<\/p>\n\n\n\n
ECC
Leverages discrete logarithm characteristics<\/p>\n\n\n\n
El Gamal
Used in recent versions of PGP<\/p>\n\n\n\n
DSA
A Federal Information Processing Standard for digital signatures (FIPS 186)<\/p>\n\n\n\n
Hash Algos
MD5 – SHA1 – SHA256 – FORK256 – RIPEMD160 – GOST – TIGER<\/p>\n\n\n\n
MD5
128 Bit Hash Value<\/p>\n\n\n\n
SHA1
160 Bit Hash Value<\/p>\n\n\n\n
SHA256
256 Bit Hash Value<\/p>\n\n\n\n
FORK256
256 Bit Hash Value<\/p>\n\n\n\n
GOST
256 Bit Hash Value<\/p>\n\n\n\n
TIGER
192 Bit Hash Value<\/p>\n\n\n\n
Key Exchange Algos
Diffie Hellman (DH) – Menezes-Qu-Vanstone (MQV) – Key Exchange Algorithm (KEA) – Elliptic Curve DH (ECDH)<\/p>\n\n\n\n
RSA Encryption Formula
C = Me % n<\/p>\n\n\n\n
RSA Decryption Formula
P = Cd % n<\/p>\n\n\n\n
EC Formula
y2 = x3 + Ax + B<\/p>\n\n\n\n
Symmetric Decryption Formula
P = D(k,c)<\/p>\n\n\n\n
Symmetric Encryption Formula
C = E(k,p)<\/p>\n\n\n\n
Cipher disk invented by _ in Year __<\/strong> Vigenere Cipher invented by _ in _<\/em><\/strong> Year Playfair Cipher invented by _ in _<\/em><\/strong> Year 1st successful attack on the Vigenere cipher published by _ in _<\/em><\/strong> Year ADFGVX Cipher invented by _ in _<\/em><\/strong> Year Enigma Machine invented by _ in _<\/em><\/strong> Year RSA invented _ in Year _<\/em><\/strong> X.509 first use in __<\/em> Year DSA filed and attributed to _ Patent Number <\/em><\/strong>in ___<\/em> Year DSA adopted by US Government in _ Year with FIPS _<\/em><\/strong> FISH (Fibonacci Shrinking) published by _ in<\/em><\/strong> TIGER was designed by _ in _<\/em><\/strong> Year AES (Rijndael) announced as replacement for DES in _ Year with FIPS _<\/em><\/strong> Electronic Code Book (ECB) Cipher Bock Chaining (CBC) Propagating Cipher Block Chaining (PCBC) Cipher Feedback (CFB) Output Feedback (OFB) Mode Counter Mode Substitution Trapdoor Diffusion which two symmetric block encryption modes turn block ciphers into stream ciphers? Ciphertext Only Attack Co-Prime Differential cryptanalysis Mono-Alphabetic Ciphers Playfair Cryptosystem Prime Pseudo-random number generator Kerberos Ticket Kerberos TGS Kerberos KDC Kerberos TGT Kerberos AS Chosen Plaintext Attack What are the four general steps involved with AES? To be suitable for cryptography, what German Federal Office for Information Security (BSI) criteria level (s) should a PRNG meet? Yarrow Clustering Knowledge of the factorization of the trapdoor information in RSA computations, allows you to be able to _<\/strong> the function. What type of encryption uses different keys to encrypt and decrypt the message?<\/p>\n\n\n\n A Symmetric The most widely used asymmetric encryption algorithm is what?<\/p>\n\n\n\n A RSA Original, unencrypted information is referred to as __<\/em>.<\/p>\n\n\n\n A text Which of the following is NOT an asymmetric system?<\/p>\n\n\n\n A PGP In order for User A to send User B an encrypted message that only User B can read, User A must encrypt message with which of the following keys?<\/p>\n\n\n\n A User A’s public key The greatest weakness with symmetric algorithms is _<\/strong>.<\/p>\n\n\n\n A They are less secure than asymmetric Which of the following is generally true about block sizes?<\/p>\n\n\n\n A Smaller block sizes increase security A _<\/strong> is a function that takes a variable-size input m and returns a fixed-size string.<\/p>\n\n\n\n A Symmetric cipher Which of the following is a cryptographic protocol that allows two parties to establish a shared key over an insecure channel?<\/p>\n\n\n\n A Elliptic Curve A _<\/em><\/strong> is a digital representation of information that identifies you as a relevant entity by a trusted third party?<\/p>\n\n\n\n A Digital Signature What is the standard used by most digital certificates?<\/p>\n\n\n\n A X.509 DES uses keys of what size?<\/p>\n\n\n\n A 56 bits Which of the following is NOT a key size used by AES?<\/p>\n\n\n\n A 512 bits Which of the following was a multi alphabet cipher widely used from the 16th century (1553) to the early 20th century (1900s)?<\/p>\n\n\n\n A Vigenere Which of the following is a substitution cipher used by ancient Hebrew scholars?<\/p>\n\n\n\n A Caesar Shifting each letter in the alphabet a fixed number of spaces to the right or left is an example of what?<\/p>\n\n\n\n A Bit shifting Which of the following most accurately defines encryption?<\/p>\n\n\n\n A changing a message so it can only be easily read by the intended recipient<\/p>\n\n\n\n B Making binary changes to a message to conceal it<\/p>\n\n\n\n C changing a message using complex mathematics<\/p>\n\n\n\n D Applying keys to plain text If you use substitution alone, what weakness is present in the resulting cipher text?<\/p>\n\n\n\n A It is the same length as the original text _<\/strong> uses at least two different shifts, changing the shift with different letters in the plain text.<\/p>\n\n\n\n A Atbash __<\/em> was designed to provide built in cryptography for the clipper chip.<\/p>\n\n\n\n A Blowfish Which of the following uses an 80 bit key on 64 bit blocks?<\/p>\n\n\n\n A Twofish With _<\/strong>, the message is divided into blocks and each block is encrypted separately. This is the most basic mode for symmetric encryption.<\/p>\n\n\n\n A Electronic codebook (ECB) Which of the following is an example of an unbalanced Feistel?<\/p>\n\n\n\n A 3DES This process is done by having each block of plaintext is XORed with the previous ciphertext block before being encrypted.<\/p>\n\n\n\n A Output feedback (OFB) The process wherein the ciphertext block is encrypted then the ciphertext produced is XOR’d back with the plaintext to produce the current ciphertext block is called what?<\/p>\n\n\n\n A Output feedback (OFB) This is a method for turning a block cipher into a stream cipher by generating a keystream block, which are then XORed with the plaintext blocks to get the ciphertext.<\/p>\n\n\n\n A Cipher feedback (CFB) Which of the following modes can be used to turn a block cipher into a stream cipher?<\/p>\n\n\n\n A Propagating cipher-block chaining (PCBC) and Electronic codebook (ECB)<\/p>\n\n\n\n B Counter Mode (CTR) and Propagating cipher-block chaining (PCBC)<\/p>\n\n\n\n C Electronic codebook (ECB) and Output feedback (OFB)<\/p>\n\n\n\n D Output feedback (OFB) and Counter Mode (CTR) A fixed-size pseudorandom number that is fed into a symmetric cipher to increase randomness is called what?<\/p>\n\n\n\n A IV A number that is used only one time then discarded is called what?<\/p>\n\n\n\n A Nonce Which of the following is a stream cipher that uses variable length key from 1 to 256 bytes?<\/p>\n\n\n\n A RC4 This algorithm was published by the German engineering firm Seimans in 1993. It is a software based stream cipher using Lagged Fibonacci generator along with a concept borrowed from the shrinking generator ciphers.<\/p>\n\n\n\n A RC4 Which of the following is NOT required for a hash?<\/p>\n\n\n\n A Minimum key length of 256 bits A __<\/strong> refers to a situation where two different inputs yield the same output.<\/p>\n\n\n\n A Substitution What is a salt?<\/p>\n\n\n\n A Key rotation<\/p>\n\n\n\n B Random bits intermixed with a hash to increase randomness and reduce collisions.<\/p>\n\n\n\n C Random bits intermixed with a symmetric cipher to increase randomness and make it more secure.<\/p>\n\n\n\n D Key whitening RFC 1321 describes what hash?<\/p>\n\n\n\n A RIPEMD What size block does FORK256 use?<\/p>\n\n\n\n A 256 In 1977 researchers at MIT described what asymmetric algorithm?<\/p>\n\n\n\n A RSA What is the formula (M^e)(%n) related to?<\/p>\n\n\n\n A Encrypting with EC Which of the following equations is related to EC?<\/p>\n\n\n\n A P = Cd%n U.S. Patent 5,231,668 and FIPS 186 define what algorithm?<\/p>\n\n\n\n A AES What is X.509?<\/p>\n\n\n\n A The standard for PGP certificates What is contained in a CRL?<\/p>\n\n\n\n A Keys for RSA What does the Online Certificate Status Protocol (OCSP) provide?<\/p>\n\n\n\n A Revoked certificates In terms of cryptanalysis, what does it mean to break a cipher?<\/p>\n\n\n\n A finding a method to decrypt a message that is at least twice as efficient as brute force<\/p>\n\n\n\n B trying every possible key until you can decrypt the message<\/p>\n\n\n\n C deploying an algorithm that uses a 228 bit key<\/p>\n\n\n\n D finding any method to decrypt the message that is more efficient than brute force An authentication method that periodically re-authenticates the client by establishing a hash that is then resent from the client is called __<\/strong>.<\/p>\n\n\n\n A PAP What is a TGS?<\/p>\n\n\n\n A The server that grants Kerberos tickets What is Kerchoff’s principle?<\/p>\n\n\n\n A A minimum key size of 256 bits is necessary for security. Which of the following is a fundamental principle of cryptography that holds that the algorithm can be publically disclosed without damaging security?<\/p>\n\n\n\n A Babbage’s principle A process that puts a message into the least significant bits of a binary file is called what?<\/p>\n\n\n\n A Symmetric cryptography If you wished to see a list of revoked certificates from a CA, where would you look?<\/p>\n\n\n\n A CRL Which of the following is generally true about block ciphers?<\/p>\n\n\n\n A Secret block ciphers should be trusted. What does the OCSP protocol provide?<\/p>\n\n\n\n A encryption U.S. encryption standard that replaced DES. Block symmetric cipher that uses 128-bit block sizes and various key lengths (128, 192, 256). DES, 3DES, SHA, AES (some AES implementations are Type I) Encryption method where the sender and receiver use an instance of the same key for encryption and decryption purposes. Block symmetric algorithm chosen by NIST as an encryption standard in 1976. It uses a 56-bit true key bit size, 64-bit block size, and 16 rounds of computation. technical specification indicating how multimedia data and e-mail binary attachments are to be transferred. Valid data transmission is maliciously or fraudulently repeated to allow an entity gain unauthorized access. protocol suite provides a method of setting up a secure channel for protected data exchange between two devices. Juniper (block cipher) Component of a PKI that creates and maintains digital certificates throughout their life cycles. Uses public key encryption and provides data encryption, server authentication, message integrity, and optional client authentication. Manipulating individuals so that they will divulge confidential information, rather than by breaking in or using technical cracking techniques. Cryptanalysis attack where the attacker is assumed to have access only to a set of ciphertexts. servers and software signing, for which independent verification and checking of identity and authority is done by issuing CA it should be impossible for any attacker to calculate, or otherwise guess, from any given subsequence, any previous or future values in the sequence Cryptanalysis attack that uses identified statistical patterns. organizations for which proof of identity is required Block symmetric cipher that uses a 128-bit key and 64-bit block size. individuals, and intended for email A form of cryptanalysis applicable to symmetric key algorithms that was invented by Eli Biham and Adi Shamir.<\/p>\n\n\n\n The examination of differences in an input and how that affects the resultant difference in the output. Cryptanalysis attack where the attacker is assumed to have access to sets of corresponding plaintext and ciphertext. Carries out real-time validation of a certificate and reports back to the user whether the certificate is valid, invalid, or unknown. What is the formula Me%n related to? Plain-text is equal to the encryption function (E) with the key (k) and the ciphertext (c) being passed as parameters to that function Not certified for government use 64 bit algorithm operating at 56 bits with an 8 bit parity block AH is the authenticating protocol, and ESP is an authenticating and encrypting protocol that uses cryptographic mechanisms to provide source authentication, confidentiality, and message integrity. developed as a Russian national standard and produced fixed length outputs of 256 bits A measure of the uncertainty associated with a random variable Attempts to make the statistical frequencies of the ciphertext and actual key as complex as possible Like AES, Serpent has a block size of 128 bits and can have a key size of 128, 192, or 256 bits. The algorithm is also a substitution-permutation network like AES. It uses 32 rounds working with a block of four 32-bit words. Each round applies one of eight 4-bit to 4-bit S-boxes 32 times in parallel. Designed by Ross Anderson, Eli Biham, and Lars Knudsen. What is the difference between Secure HTTP (SHTTP) and HTTP Secure (HTTPS)? Which of the following was a multi alphabet cipher widely used from the 16th century to the early 20th century? A _<\/strong> is a function that takes a variable-size input m and returns a fixed-size string. A small change that yields large effects in the output. Private organizations or governmental security Numbers that have no factors in common with another. Cryptanalysis attack that exploits vulnerabilities within the intrinsic algebraic structure of mathematical functions. Designed by Ross Anderson and Eli Biham in 1995. The size of a __<\/em><\/strong> hash value is 192 bits. In order for User A to send User B an encrypted message that only User B can read, User A must encrypt message with which of the following keys? Public key algorithm that can be used for digital signatures, encryption, and key exchange. Block symmetric cipher that was chosen to fulfill the Advanced Encryption Standard. It uses a 128-bit block size and various key lengths (128, 192, 256). Published by Siemens in 1993. A software-based stream cipher 128 bit hash. RFC 1321 Cipher text (C) is equal to the encryption function (E) with the key (k) and plain-text (p) being passed as parameters to that function It is impossible to compress the data such that the code is less than the Shannon entropy of the source, without it being virtually certain that information will be lost A non-secret binary vector used as the initializing input algorithm for If a cryptanalysis uncovers a method that can derive a key for an algorithm, but is only slightly faster than brute force, what is this called? It should be impossible for any attacker to calculate, or guess from an inner state of the generator, any previous numbers in the sequence or any previous inner generator states Developed by the NSA for use in the clipper chip. Skipjack uses an 80-bit key to encrypt or decrypt 64-bit data blocks.<\/p>\n\n\n\n It is an unbalanced Feistel network with 32 rounds. Algorithm that was chosen for the Data Encryption Standard, which was altered and renamed Data Encryption Algorithm. Announced by NIST as FIPS 197. Has 3 key sizes: 128, 192, 256 and all operate on 128 bit block Symmetric cipher that applies DES three times to each block of data during the encryption process. Attack that uses information (timing, power consumption) that has been gathered to uncover sensitive data or processing functions. A 160 bit hash with 3 other versions: RIPEMD-128 (128 bit), RIPEMD-256 (256 bit), RIPEMD-320 (320 bit) Transposition processes used in encryption functions to increase randomness. Used to store, distribute, and maintain cryptographic session and secret keys. Designed by Phil Zimmerman as a freeware e-mail security program and was released in 1991. It was the first widespread public key encryption program. A number that is used only one time then discarded is called what? Improvement on FISH due to vulnerability to known-plaintext attacks. Published by Ross Anderson. Stands for Menezes-Qu-Vanstone and is a protocol used for key agreement that is based on DH. Incorporated in public key standard IEEE P1363 A cryptographic protocol and infrastructure developed to send encrypted credit card numbers over the Internet. The algorithm is used identically for encryption and decryption as the data stream is simply XORed with the key. RC4 uses a variable-length key from 1 to 2048 bits, (minimum of 40 bits or higher to be considered secure).<\/p>\n\n\n\n That key constitutes a state table that is used for The payload and the routing and header information are protected in this mode. Values that are used with algorithms to increase randomness for cryptographic functions. Ticket granting service This is a variation of DES that XORs another 64-bit key to the plaintext before applying the DES algorithm.<\/p>\n\n\n\n The concept of simply XORing in an additional key is called whitening. This adds to the confusion of the resultant text. The total number of co prime numbers for a number n Naor-Reingold, Skipjack, Key Exchange Algorithm (KEA) Responsible for the accuracy of the information contained in a HTTP running over SSL. Component that keeps track of the different SAs and tells the device which one is appropriate to invoke for the different packets it receives. Which encryption standard is used primarily for mobile devices? Stream symmetric cipher that was created by Ron Rivest of RSA. Used in SSL and WEP. 256 bit and 512 bit hash Microchip installed on the motherboard of modern computers and is dedicated to carrying out security functions that involve the storage and processing of symmetric and asymmetric keys, hashes, and digital certificates. Cryptographic hash function that uses a symmetric key value and is used for data integrity and data origin authentication. Type of tunneling mechanism that provides terminal-like access to remote computers. Provides authentication and secure transmission over vulnerable channels like the Internet. Is an authentication key agreement cryptography function very similar to Diffie-Hellman. Provide authentication of a sender and integrity of a sender’s message.<\/p>\n\n\n\n A message is input into a hash function. Then the hash value is encrypted using the private key of the sender.<\/p>\n\n\n\n The result of these two steps yields a ______<\/em><\/strong><\/em><\/strong>. A 16-round Feistel cipher working on 64-bit blocks. Unlike DES, it can have varying key sizes ranging from 32 bits to 448 bits. Designed by Bruce Schneier. Which of the following modes can be used to turn a block cipher into a stream cipher? Online business transactions between companies EFS is encryption for files while Bitlocker is used for full disk encryption Cryptanalysis attack that exploits vulnerabilities within the algorithm structure. Open-community and standardized version of SSL Uses a block size of 128 bits and key sizes up to 256 bits. It is a Feistel cipher. Designed by Bruce Schneier, John Kelsey, Doug Whiting, David Wagner, Chris Hall, and Niels Ferguson. 160 bit hash Cryptographic attack that exploits the mathematics behind the birthday problem in the probability theory forces collisions within hashing functions. A process that puts a message into the least significant bits of a binary file is called what? Cryptanalysis attack that tries to uncover a mathematical problem from two different ends. Asymmetric encryption method developed in 1984. It is used in PGP implementations and GNU Privacy Guard Software. Consists of 3 parts: key generator, encryption algorithm, and decryption algorithm. A combination of the ISAKMP and OAKLEY protocols. The payload of the message is protected What did WPA replace RC4 with? N denotes natural numbers. These are also sometimes called the counting numbers. They are 1, 2, 3, etc.<\/p>\n\n\n\n Z denotes the integers. These are whole numbers such as -1, 0, 1, 2, etc. Basically, this set is the natural numbers combined with zero and the negative numbers.<\/p>\n\n\n\n Q denotes rational numbers (or the ratios of integers). They are any number that can be expressed as a ratio of two integers. Examples are 3\/2, 17\/4, and 1\/5.<\/p>\n\n\n\n R denotes real numbers. This includes the rational number as well as numbers that cannot be expressed as a ratio of two integers, such as 2\/3.<\/p>\n\n\n\n i denotes imaginary numbers. These are numbers whose square is a negative. For example, \u221a-1 = 1i. An encryption function for fixed-size blocks of data. The current generation has a block size of 128 bits (16 bytes). To encrypt with a block cipher, we need a _<\/strong><\/em><\/strong>. Don’t ever trust a _<\/em><\/strong><\/em><\/strong> or _____<\/strong><\/em><\/strong><\/em>. (Kerckhoffs’s Principle) A protocol for online shopping with a credit card. One of its features is that it encrypts the credit card number so that an eavesdropper cannot copy it. ___<\/em><\/strong><\/em><\/strong> is the worst enemy of security, and it almost always comes in the form of features or options. __<\/em><\/strong><\/em><\/strong> is a measure of how many things interact at any one point. If the effect of an option is limited to a small part of the program, then it cannot interact with an option whose effect is limited to another part of the program. The original message, m is called the __<\/em><\/strong><\/em><\/strong>. The public-key algorithms are used to establish _<\/em><\/strong>, which in turn is used to encrypt the actual data. This combines the flexibility of public-key cryptography with the efficiency of symmetric-key cryptography. Digital signatures are the public-key equivalent of __________<\/em><\/strong><\/em><\/strong>. For practical reasons, a PKI is often set up with multiple levels of CAs. There is a top-level CA, called the __<\/em><\/strong>, which issues certificates on the keys of lower-level CAs, which in turn certify the user keys. A ________<\/em><\/strong><\/em><\/strong> is what most people mean when talking about breaking an encryption system. This is the situation in which Alice and Bob are encrypting their data, and all you as the attacker get to see is the ciphertext. Trying to decrypt a message if you only know the ciphertext is called a ciphertext-only attack. This is the most difficult type of attack, because you have the least amount of information. A ____<\/em><\/strong><\/em><\/strong> is one in which you know both the plaintext and the ciphertext. The most obvious goal is to find the decryption key. A known-plaintext attack is more powerful than a ciphertext-only attack.<\/p>\n\n\n\n A True A ______<\/em><\/strong><\/em><\/strong> is any nontrivial method that detects a difference between the ideal encryption scheme and the actual one. This covers all the attacks we have discussed so far, as well as any yet-to-be-discovered attacks. A ____________________is an attack that depends on the fact that duplicate values, also called collisions, appear much faster than you would expect. An ______<\/em><\/strong><\/em><\/strong> attack is one that tries all possible values for some target object, like the key. If an attack requires 2^235 steps of work, then this corresponds to an exhaustive search for a 235-bit value. First introduced by Eli Biham in 1993, a _<\/strong><\/em><\/strong> attack assumes that the attacker has access to several encryption functions. These functions all have an unknown key, but their keys have a relationship that the attacker knows. A _<\/em><\/strong><\/em><\/strong> cipher is one for which no attack exists. An attack on a block cipher is a non-generic method of distinguishing the block cipher from an __<\/em><\/strong><\/em><\/strong> cipher. Most modern block ciphers have a __<\/em><\/strong> block size, but they operate on 32-bit words. An _<\/em><\/strong><\/em><\/strong> cipher implements an independently chosen random even permutation for each of the key values. The simplest method to encrypt a longer plaintext is known as the ___________<\/em><\/strong><\/em><\/strong>. It has serious weakness, therefore, do not use this method. _________<\/em><\/strong><\/em><\/strong> was a cylinder tool used by the Greeks, and is often specifically attributed to the Spartans. It was a physical cylinder that was used to encrypt messages. Turning the cylinder produced different ciphertexts. While it is not clear exactly how old this cipher is, it was first mentioned in the 7th century BC by the Greek poet Archilochus. The recipient uses a rod of the same diameter as the one used to create the message. He then wraps the parchment to read the message. To encrypt, one simply writes across the leather. Caesar Cipher – Every letter is shifted a fixed number of spaces to the left or the right in the alphabet. The reason it is easy to crack is the issue of letter and word frequency.<\/p>\n\n\n\n Atbash Cipher – is a Hebrew code, easier to crack than Caesar, which substitutes the first letter of the alphabet for the last and the second letter for the second to the last, etc. It simply reverses the alphabet Used by Hebrew scribes copying the book of Jeremiah. Example: A becomes Z, B becomes Y, C becomes X, etc.<\/p>\n\n\n\n Affine Cipher – is any single-substitution alphabet cipher (also called mono-alphabet substitution) in which each letter in the alphabet is mapped to some numeric value, permuted with some relatively simple mathematical function, and then converted back to a letter. The formula for Affine is: ax + b (mod M). M=26, x=Plaintext numerical equivalent, b=the shift, a=some multiple. For Caesar a=1.<\/p>\n\n\n\n Rot13 Cipher – is another single alphabet substitution cipher. It is, in fact, the simplest of all of them. It is really just a permutation of the Caesar cipher. All characters are rotated 13 characters through the alphabet. Homophonic substitution was one of the earlier attempts to make substitution ciphers more robust by_________ the letter frequencies. In World War II, the Germans used this as an electromechanical rotor-based cipher system. The machine was designed so that when the operator pressed a key, the encrypted ciphertext for that plaintext was altered each time. So, if the operator pressed the A key, he or she might generate an F in the ciphertext, and the next time, it might be a D. Essentially, this was a multi-alphabet cipher consisting of 26 possible alphabets. Cipher Disk – The cipher disk, like Scytale, is a physical device used to encrypt. The cipher disk was invented by Leon Alberti in 1466. The cipher disk was polyalphabetic; each time you turned the disk, you used a new cipher. It was literally a disk you turned to encrypt plaintext.<\/p>\n\n\n\n Vigen\u00e8re Cipher – is perhaps the most widely known multi-alphabet substitution cipher. At one time, multi-alphabet substitution was considered quite secure. In fact, the Vigen\u00e8re cipher was used in the 1800s and early 1900s. The Vigen\u00e8re cipher was invented in 1553 by Giovan Battista Bellaso. It is a method of encrypting alphabetic text by using a series of different Caesar ciphers based on the letters of a keyword. This is a very effective multi-alphabet cipher and prior to the advent of computers was considered quite strong. It should be noted that the longer the keyword, the more alphabets used to encrypt the message, and thus the stronger the encryption. In fact, one does not even need to use a real word. Any series of letters will work. In 1863, Friedrich Kasiski was the first person to publish a successful general attack on the Vigen\u00e8re cipher.<\/p>\n\n\n\n Playfair Cipher – invented in 1854 by Charles Wheatstone. It was named after Lord Playfair who promoted the use of the cipher. uses a five-by-five table containing a keyword or key phrase. To generate the key table, one would first fill in the spaces in the table with the letters of the keyword (dropping any duplicate letters), then fill the remaining spaces with the rest of the letters of the alphabet in order. People often omitted Q from the list. To encrypt a message, you would break the message into groups of two letters. For example, “CheeseBurger” becomes “Ch ee se Bu rg er”, and then you would be map out on the key table. If both letters are the same (or only one letter is left), add an “X” after the first letter. Encrypt the new pair and continue. If the letters appear on the same row of your table, replace them with the letters to their immediate right. If the letters appear on the same column of your table, replace them with the letters immediately below.<\/p>\n\n\n\n ADFGVX Cipher – This was the first cipher used by the German Army during World War I. It was invented by Colonel Fritz Nebel in 1918. This was a transposition cipher which used a modified Polybius square with a single columnar transposition used to encode a 36-letter alphabet. This was actually an extension of an earlier cipher called ADFGX. The key for this algorithm is a six-by-six square of letters. This is known as a Polybius square. It is comprised of the letters of the alphabet and the numbers 0 through 9 distributed randomly in the square. The letters A, D, F, G, V, and X are used as coordinates for the square. _<\/em><\/strong> allows you to enter in any text, choose the historic algorithm you wish to use, then encrypt that text in a matter of seconds. Many experts believe that modern cryptography begins with _________<\/em><\/strong><\/em><\/strong> In 1949 he published a paper in the in the Bell System Technical Journal entitled Communication Theory of Secrecy Systems Shortly thereafter he and Warren Weaver published a book entitled Mathematical Theory of Communication Changes to one character in the plain text affect multiple characters in the ciphertext, unlike in historical algorithms (Caesar cipher, ATBASH, Vigen\u00e8re) where each plain text character only affects one ciphertext character. Attempts to make the relationship between the statistical frequencies of the ciphertext and the actual key as complex as possible by using a complex substitution algorithm. This term means that a small change yields large effects in the output, like an avalanche. This is Fiestel’s variation on Claude Shannon’s concept of diffusion. We will see Fiestel’s ideas used in many of the block ciphers we explore in this module. Symmetric algorithm encryption Symmetric algorithm decryption To perform the binary _<\/strong> operation, you take two binary numbers and compare them one place at a time. If both numbers have a one in both places, then the resultant number is a one. If not, then the resultant number is a zero. The binary __<\/strong> operation checks to see whether there is a one in either or both numbers in a given place. If so, then the resultant number is one. If not, the resultant number is zero. The binary __<\/strong> operation impacts your study of encryption the most. It checks to see whether there is a one in a number in a given place, but not in both numbers at that place. If it is in one number but not the other, then the resultant number is one. If not, the resultant number is zero. It has a very interesting property in that it is reversible. Most symmetric ciphers use_________ as part of their process There are two types of symmetric algorithms. They are __<\/em><\/strong><\/em><\/strong> and __<\/em><\/strong><\/em><\/strong>. A block cipher literally encrypts the data in blocks. 64-bit blocks are quite common, although some algorithms (like AES) use larger blocks. For example, AES uses a 128-bit block. Stream ciphers encrypt the data as a stream, one bit at a time. The algorithm(s) needed to encrypt and decrypt a message. The random bits used in encrypting a message. The mathematical process used to alter a message and read it unintelligible by any but the intended party. The Feistel Network Refers to the generation of sub keys from a single key. Larger block sizes increase security. A True This function is named after its inventor, the German-born physicist and cryptographer Horst Feistel. At the heart of many block ciphers is a Feistel function. So this makes it a good place to start with study of symmetric algorithms. This function forms the basis for many, if not most, block ciphers. This function starts by splitting the block of plaintext data (often 64 bits) into two parts (traditionally termed L0 and R0). Usually, the split is equal, and both sides are the same size. A variation of the Feistel network called an __<\/em><\/strong><\/em><\/strong> cipher. They use a modified structure where L0 and R0 are not of equal lengths. This means that L0 might be 32 bits and R0 could be 64 bits (making a 96-bit block of text). This variation is actually used in the Skipjack algorithm. One of the oldest of the modern symmetric ciphers is________. It was a block cipher developed by IBM in the early 1970s and used as a U.S. government standard until the 1990s. IBM had originally developed a cipher called Lucifer, which was designed by Horst Feistel. When the U.S. government began seeking a standardized encryption algorithm, IBM worked with the National Security Agency (NSA) to alter Lucifer to fit the government’s needs, thus it was created. As you may guess, it is a Feistel cipher. This is a variation of DES that simply XORs another 64-bit key to the plaintext before applying the DES algorithm. _<\/em><\/strong> is designated as FIPS 197 and can have three different key sizes. They are: 128, 192, or 256 bits. This algorithm was developed by two Belgian cryptographers, Joan Daemen and Vincent Rijmen. Unlike both DES and 3DES, it is not based on a Feistel network. This algorithm uses a substitution-permutation matrix rather than a Feistel network. It also operates on a four-by-four column-major order matrix of bytes, called the state. In the SubBytes step, each byte in the matrix is substituted for another byte using an 8-bit substitution box, called the _<\/em><\/strong><\/em><\/strong>. __<\/em><\/strong> is a symmetric block cipher that was designed in 1993 by Bruce Schneier. This cryptography algorithm is intended as a replacement for DES. Like DES, it is a 16-round Feistel cipher working on 64-bit blocks. However, unlike DES, it can have varying key sizes ranging from 32 bits to 448 bits. There are really two parts to this algorithm. The first part handles the expansion of the key. The second part actually encrypts the data. The key expansion is handled in several steps. The first step is to break the original key into a set of subkeys. Specifically, a key of no more than 448 bits is separated into 4,168 bytes. There is a P-array and four 32-bit S-boxes. The P-array contains 18 32-bit subkeys, while each S-box contains 256 entries. Like Blowfish, _<\/em><\/strong> is a symmetric key block cipher which was a finalist in the AES contest. This algorithm was designed by Ross Anderson, Eli Biham, and Lars Knudsen. It has a block size of 128 bits and can have a key size of 128, 192, or 256 bits, much like AES. The algorithm is also a substitution-permutation network like AES. It uses 32 rounds working with a block of four 32-bit words. Each round applies one of eight 4-bit to 4-bit S-boxes 32 times in parallel. It was designed so that all operations can be executed in parallel. _<\/em><\/strong> uses a block size of 128 bits and key sizes up to 256 bits. It is a Feistel cipher. It was designed by Bruce Schneier, John Kelsey, Doug Whiting, David Wagner, Chris Hall, and Niels Ferguson. Designed by NSA for the clipper chip, _<\/strong><\/em><\/strong> uses an 80-bit key to encrypt or decrypt 64-bit data blocks. It is an unbalanced Feistel network with 32 rounds. The_________________ is a block cipher. The algorithm was published in 1991 and was designed by James Massey and Xuejia Lai. It operates on 64-bit blocks and has a 128-bit key. The algorithm consists of a series of eight identical transformations (each round) and an output transformation. It was designed as a replacement for DES. ____<\/em><\/strong><\/em><\/strong> was created by David Wheeler and Roger Needham and first publicly presented in 1994. It is a simple algorithm, easy to implement in code. It is a Feistel cipher that uses 64 rounds (note this is a suggestion, it can be implemented with fewer or more rounds). The rounds should be even since they are implemented in pairs called, cycles. it uses a 128-bit key operating on a 64-bit block. It also uses a constant that is defined as 232\/the golden ratio. _<\/strong><\/em><\/strong> was invented by a team of cryptographers including Vincent Rijmen, Joan Daemen, Bart Preneel, Antoon Bosselaers, and Erik De Win. It uses a 64-bit block with a 128-bit key and operates in six rounds. The most basic encryption mode is the _____<\/em><\/strong><\/em><\/strong>. The message is divided into blocks and each block is encrypted separately. When using _<\/em><\/strong><\/em><\/strong> mode, each block of plaintext is XORed with the previous ciphertext block before being encrypted. This means there is significantly more randomness in the final ciphertext. This is much more secure than electronic codebook mode and is the most common mode. In _<\/em><\/strong><\/em><\/strong>, the previous ciphertext block is encrypted then the ciphertext produced is XORed back with the plaintext to produce the current ciphertext block. Essentially it loops back on itself, increasing the randomness of the resultant ciphertext.<\/p>\n\n\n\n Allows encryption of partial blocks rather than requiring full blocks The _<\/em><\/strong><\/em><\/strong> mode turns a block cipher into a synchronous stream cipher. It generates keystream blocks, which are then XORed with the plaintext blocks to get the ciphertext. ______<\/em><\/strong><\/em><\/strong>) is also used to turn a block cipher into a stream cipher. This is much like OFB mode. CTR generates the next keystream block by encrypting successive values of a “counter.” The counter can be any simple function that produces a sequence that is guaranteed not to repeat for a long time. An
Leon Alberti – 1466<\/p>\n\n\n\n
Giovan Battista Bellaso – 1553<\/p>\n\n\n\n
Charles Wheatstone – 1854<\/p>\n\n\n\n
Friedrich Kasiski – 1863<\/p>\n\n\n\n
Colonel Fritz Nebel – 1918<\/p>\n\n\n\n
Arthur Scherbius – 1918<\/p>\n\n\n\n
Ron Rivest, Adi Shamir, and Len Adleman – 1977<\/p>\n\n\n\n
1988<\/p>\n\n\n\n
David Kravitz – US Patent 5,231,668 – 1991<\/p>\n\n\n\n
1993 – 186<\/p>\n\n\n\n
Siemens – 1993<\/p>\n\n\n\n
Ross Anderson – 1995<\/p>\n\n\n\n
2001 – 197<\/p>\n\n\n\n
Each block is encrypted independently, BUT identical plaintext blocks are encrypted into identical ciphertext blocks<\/p>\n\n\n\n
Each block of plaintext is XORed with the previous ciphertext block before being encrypted. This way, each ciphertext block depends on all plaintext blocks processed up to that point. To make each message unique, an initialization vector must be used in the first block.<\/p>\n\n\n\n
Each block of plaintext is XoRed with the XOR of the previous plaintext block and the previous ciphertext block before being encrypted. As with CBC mode, an initialization vector is used in the first block.<\/p>\n\n\n\n
Allows encryption of partial blocks rather than requiring full blocks for encryption. This eliminates the need to pad a block like in CBC.<\/p>\n\n\n\n
Makes a block cipher into a synchronous stream cipher. It generates keystream blocks, which are then XORed with the plaintext blocks to get the ciphertext.<\/p>\n\n\n\n
Turns a block cipher into a stream cipher. It generates the next keystream block by encrypting successive values of a “counter”.<\/p>\n\n\n\n
involves XORing the plaintext message with the key?<\/p>\n\n\n\n
allows RSA to be used for both encryption and digital signatures.<\/p>\n\n\n\n
a change in in one bit in the plaintext would affect multiple characters in the ciphertext<\/p>\n\n\n\n
OFB – CTR<\/p>\n\n\n\n
an attack in which the attacker only has access to the ciphertext of a message?<\/p>\n\n\n\n
a number that only shares the number 1 as a common factor with another?<\/p>\n\n\n\n
involves the examination of differences in an input and how that affects the resultant difference in output<\/p>\n\n\n\n
Atbash – Scytale – ROT-13<\/p>\n\n\n\n
Cipher makes use of a 5×5 table containing a keyword or key phrase and encrypts pairs of letters or digraphs<\/p>\n\n\n\n
represents the entire cryptographic operation i.e. the algorithm, key, and key management functions<\/p>\n\n\n\n
number whose factors are 1 and itself?<\/p>\n\n\n\n
a mechanism used to create number streams with random properties. Examples include Lagged Fibonacci and Mersenne Twister<\/p>\n\n\n\n
Used to authenticate. Contains the identity of the client, the session key, timestamp, and checksum<\/p>\n\n\n\n
Issues tickets<\/p>\n\n\n\n
Server that provides the initial ticket<\/p>\n\n\n\n
The ticket that is granted during the authentication process<\/p>\n\n\n\n
Server that authorizes the principal and connects them to the ticket granting server<\/p>\n\n\n\n
an attack in which the attacker obtains ciphertext corresponding to a set of plaintexts to use in an attempt to derive the key used<\/p>\n\n\n\n
Rounds – Initial Round – Final Round – Key Expansion<\/p>\n\n\n\n
K3 & K4<\/p>\n\n\n\n
an algorithm that generates PRNG outputs and employs a reseed mechanism to reseed the key periodically with new entries from one of the two entropy pool employed<\/p>\n\n\n\n
An instance where different encryption keys generate the same ciphertext from the same plaintext message<\/p>\n\n\n\n
Invert<\/p>\n\n\n\n
B Private key
C Secure
D Asymmetric
D<\/p>\n\n\n\n
B Vigenere
C DES
D Caesar Cipher
A<\/p>\n\n\n\n
B plaintext
C cleantext
D ciphertext
B<\/p>\n\n\n\n
B RSA
C SSL
D DES
D<\/p>\n\n\n\n
B User A’s private key
C User B’s public key
D User B’s private key
C<\/p>\n\n\n\n
B The problem of key exchange
C They are slower than asymmetric
D The problem of generating keys
B<\/p>\n\n\n\n
B Block sizes must be more than 256 bits to be secure
C Block size is irrelevant to security
D Larger block sizes increase security
D<\/p>\n\n\n\n
B Hash
C Asymmetric cipher
D Feistel
B<\/p>\n\n\n\n
B RSA
C MD5
D Diffie-Hellman
D<\/p>\n\n\n\n
B Hash
C Ownership stamp
D Digest
A<\/p>\n\n\n\n
B CRL
C RFC 2298
D OCSP
A<\/p>\n\n\n\n
B 192 bits
C 128 bits
D 64 bits
A<\/p>\n\n\n\n
B 128 bits
C 192 bits
D 256 bits
A<\/p>\n\n\n\n
B Caesar
C Atbash
D Scytale
A<\/p>\n\n\n\n
B Vigenere
C Scytale
D Atbash
D<\/p>\n\n\n\n
B Confusion
C Multi substitution
D Single substitution
D<\/p>\n\n\n\n
A<\/p>\n\n\n\n
B It is easily broken with modern computers.
C It is too simple.
D Because it maintains letter and word frequency.
D<\/p>\n\n\n\n
B multi-alphabet encryption
C Scytale
D Caesar cipher
B<\/p>\n\n\n\n
B Skipjack
C GOST
D 3DES
B<\/p>\n\n\n\n
B AES
C Skipjack
D DES
C<\/p>\n\n\n\n
B Cipher-block chaining (CBC)
C Cipher feedback (CFB)
D Output feedback (OFB)
A<\/p>\n\n\n\n
B Skipjack
C Twofish
D AES
B<\/p>\n\n\n\n
B Cipher-block chaining (CBC)
C Electronic codebook (ECB)
D Cipher feedback (CFB)
B<\/p>\n\n\n\n
B Cipher-block chaining (CBC)
C Cipher feedback (CFB)
D Electronic codebook (ECB)
C<\/p>\n\n\n\n
B Electronic codebook (ECB)
C Output feedback (OFB)
D Cipher-block chaining (CBC)
C<\/p>\n\n\n\n
D<\/p>\n\n\n\n
B Key
C Chain
D Salt
A<\/p>\n\n\n\n
B Chain
C Salt
D IV
A<\/p>\n\n\n\n
B AES
C DESx
D DES
A<\/p>\n\n\n\n
B Blowfish
C FISH
D Twofish
C<\/p>\n\n\n\n
B Variable-length input, fixed-length output
C Non-reversible
D Few collisions
A<\/p>\n\n\n\n
B Convergence
C Collision
D Transposition
C<\/p>\n\n\n\n
B<\/p>\n\n\n\n
B SHA1
C GOST
D MD5
D<\/p>\n\n\n\n
B 128
C 512
D 64
C<\/p>\n\n\n\n
B AES
C DH
D EC
A<\/p>\n\n\n\n
B Generating Mersenne primes
C Decrypting with RSA
D Encrypting with RSA
C<\/p>\n\n\n\n
B Me%n
C y2 = x3 + Ax + B
D Let m = (p-1)(q-1)
C<\/p>\n\n\n\n
B RSA
C Elliptic Curve (EC)
D Digital Signature Algorithm (DSA)
D<\/p>\n\n\n\n
B The standard for encrypting email
C The standard for FIPS 186
D The standard for digital certificates
D<\/p>\n\n\n\n
B New certificates
C Revoked certificates
D Keys for AES
C<\/p>\n\n\n\n
B Hashing
C VPN connectivity
D Encryption
A<\/p>\n\n\n\n
D<\/p>\n\n\n\n
B CHAP
C SPAP
D EAP
B<\/p>\n\n\n\n
B protocol for encryption
C protocol for key exchange
D The server that escrows keys
A<\/p>\n\n\n\n
B Both algorithm and key should be kept secret.
C A minimum of 15 rounds is needed for a Feistel cipher to be secure.
D Only the key needs to be secret, not the actual algorithm.
D<\/p>\n\n\n\n
B Kerkchoff’s principle
C Vigenere’s principle
D Shamir’s principle
B<\/p>\n\n\n\n
B Masking
C Steganography
D Asymmetric cryptography
C<\/p>\n\n\n\n
B CA
C RFC
D RA
A<\/p>\n\n\n\n
B Block ciphers permute the bits of the input plaintext.
C The plaintext and ciphertext are always the same size.
D A block cipher is an encryption function for variable-size blocks of data.
C<\/p>\n\n\n\n
B VPN connectivity
C hashing
D a real time protocol for verifying certificates
D<\/p>\n\n\n\n
AES<\/p>\n\n\n\n
Class 3 Algorithms<\/p>\n\n\n\n
Symmetric<\/p>\n\n\n\n
Data Encryption Standard (DES)<\/p>\n\n\n\n
Multipurpose Internet Mail Extensions (MIME)<\/p>\n\n\n\n
Replay Attack<\/p>\n\n\n\n
Internet Protocol Security (IPSec)<\/p>\n\n\n\n
MAYFLY (asymmetric)
FASTHASH (hashing)
WALBURN (high bandwith link encryption)
PEGASUS (satellite telemetry)
Class 1 Algorithms<\/p>\n\n\n\n
Certificate Authority<\/p>\n\n\n\n
It is currently at version 3.0.
Secure Sockets Layer (SSL)<\/p>\n\n\n\n
Social engineering attack<\/p>\n\n\n\n
Ciphertext-only attack<\/p>\n\n\n\n
Class 3 Certificates<\/p>\n\n\n\n
BSI Criteria K3 states<\/p>\n\n\n\n
Statistical attack<\/p>\n\n\n\n
Class 2 Certificates<\/p>\n\n\n\n
International Data Encryption Algorithm (IDEA)<\/p>\n\n\n\n
Class 1 Certificates<\/p>\n\n\n\n
Differential cryptanalysis<\/p>\n\n\n\n
Known plaintext attack<\/p>\n\n\n\n
OCSP checks the CRL that is maintained by the CA.
Online Certificate Status Protocol (OCSP)<\/p>\n\n\n\n
Encrypting with RSA<\/p>\n\n\n\n
P= E(k,c) Symmetric decryption<\/p>\n\n\n\n
Class 4 algorithms<\/p>\n\n\n\n
DES<\/p>\n\n\n\n
Authentication Header (AH) and Encapsulating Security Payload (ESP).<\/p>\n\n\n\n
GOST<\/p>\n\n\n\n
Entropy<\/p>\n\n\n\n
Confusion<\/p>\n\n\n\n
Serpent<\/p>\n\n\n\n
S-HTTP is a technology that protects each message sent between two computers, while HTTPS protects the communication channel between two computers, messages and all.<\/p>\n\n\n\n
Vigenere<\/p>\n\n\n\n
Hash<\/p>\n\n\n\n
Avalanche<\/p>\n\n\n\n
Class 5 Certificates<\/p>\n\n\n\n
Co-prime numbers<\/p>\n\n\n\n
Algebraic attack<\/p>\n\n\n\n
TIGER<\/p>\n\n\n\n
User B’s public key<\/p>\n\n\n\n
an extension of the Diffie-Hellman algorithm.
El Gamal<\/p>\n\n\n\n
Rijndael<\/p>\n\n\n\n
using a Lagged Fibonacci generator (pseudorandom number generator).
FISH<\/p>\n\n\n\n
MD5<\/p>\n\n\n\n
C = E(k,p) Symmetric encryption<\/p>\n\n\n\n
Shannon’s source coding theorem<\/p>\n\n\n\n
the encryption of a plaintext block sequence to increase security by introducing additional cryptographic variance.
IV (Initialization Vector)<\/p>\n\n\n\n
Success<\/p>\n\n\n\n\n
PKI services<\/li>\n<\/ul>\n\n\n\n
BSI criteria K4 states:<\/p>\n\n\n\n
Skipjack<\/p>\n\n\n\n
Lucifer<\/p>\n\n\n\n
AES<\/p>\n\n\n\n
Triple DES (3DES)<\/p>\n\n\n\n
Side-channel attack<\/p>\n\n\n\n
RIPEMD-160<\/p>\n\n\n\n
Diffusion<\/p>\n\n\n\n
Key Distribution Center (KDC)<\/p>\n\n\n\n
Pretty Good Privacy (PGP)<\/p>\n\n\n\n
Nonce<\/p>\n\n\n\n
PIKE<\/p>\n\n\n\n
MQV<\/p>\n\n\n\n
Secure Electronic Transaction (SET)<\/p>\n\n\n\n
the subsequent generation of pseudo-random bytes and then to generate
RC4<\/p>\n\n\n\n
Tunnel mode<\/p>\n\n\n\n
Initialization vectors (IVs)<\/p>\n\n\n\n
TGS<\/p>\n\n\n\n
DESx<\/p>\n\n\n\n
Euler’s Totient<\/p>\n\n\n\n
Mersenne Twister,
Linear Congruential Generator,
Lehmer Random Number Generator (twisted generalized feedback shift registers),
Lagged Fibonacci Generator (LFG)
Examples of PRNGs (pseudo random number generators)<\/p>\n\n\n\n
Class 2 Algorithms<\/p>\n\n\n\n
certificate request. The ___<\/em><\/strong><\/em><\/strong> is a proxy for the CA and also expected to perform user validation before issuing a certificate request.
Registration authority (RA)<\/p>\n\n\n\n
HTTP Secure (HTTPS)<\/p>\n\n\n\n
security parameter index (SPI)<\/p>\n\n\n\n
ECC<\/p>\n\n\n\n
RC4<\/p>\n\n\n\n
SHA-2<\/p>\n\n\n\n
Trusted Platform Module (TPM)<\/p>\n\n\n\n
Hashed message authentication code (HMAC)<\/p>\n\n\n\n
Secure Shell (SSH)<\/p>\n\n\n\n
MQV (Menezes-Qu-Vanstone)<\/p>\n\n\n\n
Digital Signature<\/p>\n\n\n\n
Blowfish<\/p>\n\n\n\n
Output feedback (OFB) and Counter Mode (CTR)<\/p>\n\n\n\n
Class 4 certificates<\/p>\n\n\n\n
EFS vs. Bitlocker<\/p>\n\n\n\n
Analytic attack<\/p>\n\n\n\n
but TLS is more extensible and is backward compatible with SSL.
Transport-Layer Security (TLS)<\/p>\n\n\n\n
Twofish<\/p>\n\n\n\n
SHA-1<\/p>\n\n\n\n
Birthday attack<\/p>\n\n\n\n
Steganography<\/p>\n\n\n\n
Meet-in-the-middle attack<\/p>\n\n\n\n
El Gamal<\/p>\n\n\n\n
Internet Key Exchange (IKE)<\/p>\n\n\n\n
Transport mode<\/p>\n\n\n\n
TKIP (Temporal Key Integrity Protocol)<\/p>\n\n\n\n
Explain the number groupings: N, Z, Q, R, i<\/p>\n\n\n\n
block cipher<\/p>\n\n\n\n
secret key<\/p>\n\n\n\n
secret block cipher; secret algorithm<\/p>\n\n\n\n
SET<\/p>\n\n\n\n
Complexity<\/p>\n\n\n\n
Complexity<\/p>\n\n\n\n
plaintext<\/p>\n\n\n\n
a secret key<\/p>\n\n\n\n
message authentication codes<\/p>\n\n\n\n
root<\/p>\n\n\n\n
ciphertext-only attack<\/p>\n\n\n\n
known-plaintext attack<\/p>\n\n\n\n
B False
A<\/p>\n\n\n\n
distinguishing attack<\/p>\n\n\n\n
Birthday attack<\/p>\n\n\n\n
exhaustive search<\/p>\n\n\n\n
related-key<\/p>\n\n\n\n
secure block<\/p>\n\n\n\n
ideal block<\/p>\n\n\n\n
128-bit<\/p>\n\n\n\n
ideal block<\/p>\n\n\n\n
electronic codebook mode (ECB)<\/p>\n\n\n\n
Scytale<\/p>\n\n\n\n
Examples of Mono-Alphabet Substitution<\/p>\n\n\n\n
masking<\/p>\n\n\n\n
The Enigma Machine<\/p>\n\n\n\n
Examples of poly-alphabetic substitution<\/p>\n\n\n\n
CrypTool<\/p>\n\n\n\n
Claude Shannon<\/p>\n\n\n\n
Diffusion<\/p>\n\n\n\n
Confusion<\/p>\n\n\n\n
Avalanche<\/p>\n\n\n\n
C = E(k,p)<\/p>\n\n\n\n
P = D(k,c)<\/p>\n\n\n\n
AND<\/p>\n\n\n\n
OR<\/p>\n\n\n\n
XOR<\/p>\n\n\n\n
XORing<\/p>\n\n\n\n
block ciphers; stream ciphers<\/p>\n\n\n\n
Cipher<\/p>\n\n\n\n
Key<\/p>\n\n\n\n
Algorithm<\/p>\n\n\n\n
DES
3DES
AES
Blowfish
Serpent
Twofish
Skipjack
IDEA
CAST
TEA
SHARK
Symmetric Block Cipher Algorithms<\/p>\n\n\n\n
Key schedule<\/p>\n\n\n\n
Larger key sizes increase security.
If the round function is secure, then more rounds increase security.<\/p>\n\n\n\n
B False
A<\/p>\n\n\n\n
The Feistel Function<\/p>\n\n\n\n
Unbalanced Feistel<\/p>\n\n\n\n
DES<\/p>\n\n\n\n
DESx<\/p>\n\n\n\n
AES<\/p>\n\n\n\n
Rijndael S-box<\/p>\n\n\n\n
Blowfish<\/p>\n\n\n\n
Serpent<\/p>\n\n\n\n
Twofish<\/p>\n\n\n\n
Skipjack<\/p>\n\n\n\n
International Data Encryption Algorithm (IDEA)<\/p>\n\n\n\n
TEA, or Tiny Encryption Algorithm<\/p>\n\n\n\n
SHARK<\/p>\n\n\n\n
electronic codebook (ECB) mode<\/p>\n\n\n\n
cipher-block chaining (CBC)<\/p>\n\n\n\n
for encryption. This eliminates the need to pad a block like in CBC.
cipher feedback mode (CFB)<\/p>\n\n\n\n
output feedback (OFB)<\/p>\n\n\n\n
Counter mode (CTR<\/p>\n\n\n\n