Is 128-bit RC4 secure?
AES-128 is considered more secure than RC4. RC4 is an old stream cipher which is considered broken.
What is RC4 key size?
1 to 256 bytes
RC4 is a stream cipher with a secret key whose length is 1 to 256 bytes.
What is the block size for RC4?
RC4, in particular, is a variable key-size stream cipher using 64-bit and 128-bit sizes.
What is the highest number of bits RC4 encrypted by?
The algorithm operates on a user-selected variable-length key(K) of 1 to 256 bytes (8 to 2048 bits), typically between 5 and 16 bytes.
Is RC4 safe?
The vulnerabilities found in RC4 means RC4 is extremely insecure, so very few applications use it now. RC4 cannot be used on smaller streams of data, so its usage is more niche than other stream ciphers.
Is RC4 recommended?
Microsoft and Mozilla have issued similar recommendations to retire and deprecate the RC4 cipher as well as other weak algorithms such as SHA-1. Microsoft recommends TLS 1.2 with AES-GCM as a more secure alternative while providing similar performance.
Does TLS 1.0 use RC4?
After the BEAST attack was disclosed in 2011, we—grudgingly—started using RC4 in order to avoid the vulnerable CBC suites in TLS 1.0 and earlier. This caused the usage of RC4 to increase, and some say that it now accounts for about 50% of all TLS traffic.
Does RC4 use IV?
Traditional stream ciphers such as RC4 do not support an explicit IV as input, and a custom solution for incorporating an IV into the cipher’s key or internal state is needed. Some designs realized in practice are known to be insecure; the WEP protocol is a notable example, and is prone to related-IV attacks.
Does Google use RC4?
Google was using RC4 by default before BEAST, simply because it’s the lowest CPU burden to implement and they were leading the way in SSL-by-default, so at their scale this really mattered.
What is wrong with RC4?
So what’s wrong with RC4? Like all stream ciphers, RC4 takes a short (e.g., 128-bit) key and stretches it into a long string of pseudo-random bytes. These bytes are XORed with the message you want to encrypt, resulting in what should be a pretty opaque (and random-looking) ciphertext.