Advantages and disadvantages of Stream versus Block Ciphers
2011年1月14日 · A stream cipher can be converted into a Pseudorandom Number Generator by encrypting a long sequence of bytes of value zero. Actually, many (but not all) stream ciphers internally work by being a PRNG, generating a long sequence of key-dependent pseudo-random bytes, which is subsequently combined (by bitwise XOR) with the data to encrypt (or ...
cryptography - How to choose a stream cipher - Information …
2011年6月16日 · For these, one could remark that a block cipher is a versatile primitive, and that maybe an algorithm designed specifically to encrypt long streams, but unable to do anything else, could possibly crunch data a bit more faster. These are called stream ciphers. An old, well-known, slightly weak and actually not that fast stream cipher is RC4.
Using AES as a Stream Cipher - Information Security Stack Exchange
2014年8月11日 · Because of this, I'm thinking I can increase throughput by using AES as a stream cipher. The solution I came up with is simply to use the key to encrypt a message of all 0's with size rounded up to the nearest 128 bits, using AES and a suitable non-authenticated encryption mode like CTR.
Why can't you use True Random Number Generator (TRNG) to …
2022年2月10日 · The key stream used to encrypt or decrypt any given message is exactly the length of that message. The operation of a stream cipher function is essentially to "stretch" the key to an arbitrary-length key stream. Directly used for encryption and decryption. Typically, the key stream is XORed with the plaintext to generate ciphertext (encryption).
How is the stream cipher key shared on GSM?
2022年5月3日 · I read that phones encrypt communication (GSM as implemented in 2G,3G..) - particularly voice as SMS are unencrypted - using a stream cipher. Symmetric Stream ciphers use the flip-flop machinery to start (a true random generator imho), and then they follow some algorithm to change message bitwise ( and can be broken with simple linear algebra ...
encryption - Does the terms stream and block ciphers apply to …
2017年12月15日 · But they're not so; "block cipher" and "stream cipher" are two fairly narrow types of object that have simply been of great interest to modern cryptographers. There are designs that are based on different, less well-known concepts, e.g. the concept of an enciphering schemes that serves as the foundation for AEZ , one of the current candidates ...
What are some examples of a block cipher's versatility over a …
The eSTREAM competition resulted in a portfolio of seemingly secure stream ciphers which indeed happen to be faster than AES-based encryption on a number of architectures (e.g. on a 2.4 GHz Core2 x86 CPU, I can do AES at 160 MBytes/s, while the Sosemanuk stream cipher reaches 700 MBytes/s on the same hardware).
Decrypt cipher texts encypted with the same one time pad key
2014年1月14日 · If the two encrypted messages are using the same stream cipher and the same key, C1 xor C2 results in M1 xor M2 where C1 and C2 are the respective ciphertext and M1 and M2 are the corresponding plaintext. You can then recover the plaintext using a technique known as crib dragging.
compliance - Why are CHACHA20 TLS ciphers not compliant with …
2024年12月14日 · The topic of standardizing a stream cipher especially for resource-constrainted environments has been discussed within the NIST since at least 2011. In the Lightweight Crypto Standardization Process, there was at least one stream cipher (Grain-128AEAD) which made it to the final round, but ultimately, it lost to a block cipher. So the NIST ...
What type of cipher is RSA? - Information Security Stack Exchange
2011年1月25日 · RC4 stream cipher: A symmetric cipher that converts a short shared secret into a pseudorandom number generator (keystream) to encrypt data. Invented as a RSA trade-secret in 1987 and leaked in 1994. RC2, RC5 and RC6 block ciphers: Block ciphers encrypt a single small block according to the shared secret - the core design trick being on how the ...