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Cards in this deck (14)
- 1Symmetric EncryptionMethod of encrypting data to move large amounts of data.
Strenghts: Fast, Secure
Weakness: Same key used for encrypting and decrypting - 2Symmetric Encryption: StrengthsFast and secure, provided the key size is large.
- 3Symmetric Encryption: WeaknessesSame key is used for encryption and decryption.
This key must be securely sahred before encryption can start, and must be kept safe for as long as encryption is needed. - 42 types of: Symmetric Encryption-Those that use 'block cipher'
- Those that use a 'streaming cipher' - 5Block Cipher-Method of encrypting text in which a cryptographic key and algorithm are applied to a block of data at once as a group rather than to one bit at a time.
-Block cipher is a symmetric encryption. - 6Stream CipherSummetric key cipher where plaintext digits are combined with a pseudorandom digit stream.
-Each plaintext digit is encrypted individually
-Because the encryption of each digit is dependent on the current state of the cipher, it is known as a state cipher.
-In actual use the digit is usually a bit and combined with XOR (exclusive-or) - 7DESData Encryption Standard (DES)
-Symmetric encryption using a BLOCK cipher.
-Block size is 64 bits
-Now considered to be insecure for many applications. Mainly because the 56-bit key size is too small.
Application: IPSEC - 83DESBasically DES x3.
-Symmetric encryption using a block cipher as well, it reuses DES implementation, by chaining three keys.
-Still believed to be secure because it requires 2^112 operations. It is not easy to brute force this encryption. - 9AESSymmetric BLOCK cipher used by the US government to protect classified information and is implemeted in software and hardware throughout the world to encrypt sensitive data.
- 10How does AES work?AES has 3 approved key lenghts: 128, 192 and 256 bits.
An algorithm starts with a random number, in which the key and data encrypted with it are scrambled through 4 rounds of mathematical processes. The key that is used to encrypt the number must also be used to decrypt it. - 11BlowfishSymmetric BLOCK cipher that can be used as a drop-in replacement for DES or IDEA. It takes a variable-length key, from 32 bits to 445 bits.
-One of the fastest block ciphers in widespread use.
-Suitable for applications where the key does not change often, like a communications link.
-Known to be susceptible to attacks on reflectively weak keys.
-Open source standard - 12RC4Symmetric encryption.
Shared key STREAM CIPHER.
Does not have very large block size - the cipher becomes inefficient to operate with very large block sizes. - 13WEPWired Equivalent Privacy (WEP)
-Based on RC4, is a STREAMING, SYMMETRIC cipher.
-Not considered secure - 14—
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- Flashcards on Untitled, created by Ali Sahar on 07/12/2015.
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- Ali Sahar
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