Difference Between AES and RC4 (With Table)

It is critical to preserve our private information while we trade information over the Web. To ensure data security, cryptographic techniques such as AES and RC4 are utilized. Cryptographers created this excellent method that is difficult for a cryptanalyst by mixing elements from mathematics and computer science.

AES vs RC4

The main difference between AES and RC4 is that they use separate ciphers. AES is blocking encryption that uses block sizes to encode plain text.  On the other hand, RC4 is a stream encryption algorithm that encrypts a bit at a time, similar to how a stream flows.

In response to imminent DES challenges, NIST started creating Advanced Encryption Standard in 1997. The top encrypting competitor was picked from among fifteen alternatives that participated in open tendering to meet AES criteria. AES employs a 128-bit component and 3 important lengths: 128, 192, and 256 bits.

Ron Rivest created the RC4 for the sake of Evading detection. It is an asymmetric encryption algorithm that encrypts plaintext by encoding it little by little with a key. Key lengths come in many sizes between 64 and 128 bits. RC4 was initially kept from the public until its release to the public. Ron’s passcode is his other identity.

Comparison Table Between AES and RC4

MeaningThe Advanced Encryption Standard is a type of symmetric block encryption.
Rivest Cipher 4 is a symmetric stream cipher.
SourceIn 1997, an open contest was held to design AES.
In 1987, Ron Rivest created RC4.
SecurityAES is a much more secure algorithm than RC4.
RC4 is much less safe than AES.
Key lengths128, 192, and 256 bits64 or 128 bits
UsesSSL, TSL, etc.NASA, NIST, etc

What is AES?

National Institute of standards hosted an equal playing field in 1997. Cryptologists from all around the world were asked to share their algorithms. They had to fulfill the AES criteria. Each one of the algorithms was examined to choose the best one. Rijndael was eventually picked as the candidate in 1999.

AES is a kind of block encryption that employs a symmetric key. To convert a plain text to ciphertext, it is encrypted in block sizes. The bit size is restricted to 128 bits, while the key sizes are 128, 192, and 256 bits. The amount of rounding is dependent on the size of the key. There are ten cycles for 128 bits, twelve rounds for 192 bits, and fourteen cycles for 256 bits. They’re known as AES128, AES192, and AES256.

Each cycle of the encryption procedure consists of four phases. The more rounds there are, the more difficult it is to break the encryption algorithm. An asymmetrical key is employed, implying that a unique key is provided mostly by the user and the receiver.

The National Institute of Standards defined the following high-security conditions:

  • It has to be a cryptographic algorithm with a symmetric key.
  • AES should have adjustable two different keys.
  • AES should always be planned in such a manner that it can be implemented into all of hardware and the software.
  • The definition of AES must be determined by the general population.

What is RC4?

Ron Rivest devised Rc4 Cipher 4 in 1987. He progressed it to consistent RSA security. The original theory was originated by a one-time pad, also known as the Verman cipher. RC4, like AES, is an asymmetric algorithm. RC4 is indeed a stream cipher, as opposed to AES. Rivest Cipher 4’s encryption was shrouded in secrecy till the code was published to the general public in 1994.

RC4 is byte-oriented stream encryption. Little by little, protect the data. Key sizes are 64-bit or 128-bit. To create the encrypted message, the encryption procedure uses two different keys such as the secret key and the RC4 algorithm.

The input sequence in RC4 is generated by KSA and PRGA. KSA is an abbreviation for Key Scheduling Algorithm, and PRGA is an abbreviation for Pseudo-Random Generating Algorithm. We implement a single ciphertext that incorporates the randomization of 256 likely bytes and two 8-bit index pointers. Similarly, decoding follows an XOR pattern.

SSL, WEP, TLS, and WPA are examples of RC4 applications. Rivest Cipher 4 variants include Splash, RC4A, VMPC, and RC4A+. The stream ciphers employed by RC4 are simple to implement and hence extensively utilized. Unlike AES, RC4 does not have rigorous security. Limited data channels can indeed be encrypted with RC4.

Main Differences Between AES and RC4

  1. The Advanced Encryption Standard is a block cipher, whereas Ron Rivest Cipher 4 is a stream cipher.
  2. In terms of security, AES outperforms RC4 in comparison.
  3. AES was created after RC4; the former was created in 1997, while the other was created in 1987.
  4. AES employs key lengths of 128, 192, and 256 bits, whilst RC4 employs key lengths of 64 and 128 bits.
  5. AES is a complicated technique, but RC4 encrypting is rather simple.


It is crucial to check the safety of our data because we use the Internet to transmit essential information. To maintain the security of our critical information, the block cipher encrypts our data. AES and RC4 are two methods that can be used to avoid data leakage.

AES is regarded as among the most complicated algorithms, which may take experts billions of years to decrypt using contemporary computer systems, whereas RC4 is an older version that first appeared in 1987, a handful of years before AES. AES is classified as a block cipher, whereas RC4 is classified as a stream cipher. AES is a freely available method that may be applied in hardware and software.

RC4 is protected by a trademark. RC4 was submerged before it was made available to the public domain. NASA and the National Institute of Standards have modified AES for high-security encryption. While SSL, Wpa, and TLS all use RC4, WPA does not (2003). AES is slower than RC4.


  1. https://ieeexplore.ieee.org/abstract/document/1258477/
  2. https://asat.journals.ekb.eg/article_23497.html