Also stream ciphers do not provide integrity

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•Also, stream ciphers do not provide integrity protection or authentication, whereas some block ciphers (depending on mode) can provide integrity protection, in addition to confidentiality. •Because of all the above, stream ciphers are usually best for cases where the amount of data is either unknown, or continuous - such as network streams. Block ciphers, on the other hand, or more useful when the amount of data is pre-known - such as a file, data fields, or request/response protocols, such as HTTP where the length of the total message is known already at the beginning. 7. A sender and receiver are using a poly-alphabetic substitution cipher. What allows them to be certain they agree on the correct alphabet for each character? A. One time pad - The One-time pad. One-time pad (OTP), also called Vernam-cipher or the perfect cipher, is a crypto algorithm where plaintext is combined with a random key. It is the only existing mathematically unbreakable encryption
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B. Key - is a piece of information (a parameter) that determines the functional output of a cryptographic algorithm C. Key space - A key space is the set of all possible key values that a particular enciphering algorithm admits. A transposition example over the English alphabet when thought of as an arbitrary permutation over the alphabet set will consist of 26! Keys, each corresponding to one permutation. D. Frequency analysis - In cryptanalysis, frequency analysis is the study of the frequency of letters or groups of letters in a cipher text. The method is used as an aid to breaking classical ciphers 8. The SSL server and client compute their right keys and initialization vectors from which key? A. The master key - A symmetric master key is used to derive other symmetric keys (e.g., data encryption keys, key wrapping keys, or authentication keys) using symmetric cryptographic methods. B. The servers if he Hellman public key. C. The clients Diffie Hellman public key - Diffie Hellman is an algorithm used to establish a shared secret between two parties. It is primarily used as a method of exchanging cryptography keys for use in symmetric encryption algorithms like AES. The algorithm in itself is very simple. Let's assume that Alice wants to establish a shared secret with Bob. D. The pre-master secret key - The point of a premaster secret is to provide greater consistency between TLS cipher suites. 9. Which piece of information is part of an SSL sessions cipher spec parameters? A. Hash algorithm - A hash function is any function that can be used to map data of arbitrary size to data of fixed size. The values returned by a hash function are called hash values, hash codes, hash sums, or simply hashes. One use is a data structure called a hash table, widely used in computer software for rapid data lookup.
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