Difference Between RSA and DSA

Technology has increased and updates a lot in few years, everything is being online or on computers. Communication or storing data everything is being digital on computers.

While when it comes to storing data, the most common problem that arises is the security of the data. We all are aware of the frauds and breaches that take place while transferring or storing data that could lead to loss. Even it causes the rise in cybercrime.

For increasing the security of these, several systems have been developed. RSA and DSA are examples of such systems. To fully understand them, the first thing is to know how both of them are different.

RSA vs DSA

The difference between RSA and DSA is that RSA stands for Rivest-Shamir-Adleman while DSA means Digital Signature Algorithm, as their name suggests they are used for various purposes, and for this, they use the different concepts of working. RSA was developed earlier than the DSA, and both of them were developed by different people. They also differ in terms of speed of decryption and encryption and their uses.

Rivest-Shamir-Adleman or popularly known as RSA, is a system used for securing the transmission of data which was developed in 1977.

It is a public-key cryptosystem. Its name was derived from the surname of its developers. It is the oldest cryptosystem used for secure data transmission and is also known as public-key cryptography.

Digital Signature Algorithm is the public key encryption algorithm used for generating the digital/electronic signature and verifies it.

It was developed after the RSA in 1991 and is considered to be best for decryption and signing in. The signature can only be made by the person who is transmitting the data.

Comparison Table

Parameters of Comparison	RSA	DSA
Meaning	Cryptosystem algorithm	Digital signature algorithm
Used for	Securing data transmission	Verification of digital signature
Developed in	1977	1991
Uses	mathematical concept	discrete logarithm and modular exponentiation
Best suited for	Verification and encryption	Decryption and signing in

What is RSA?

It is a type of asymmetric cryptography algorithm which means it uses two keys, public and private, for working. It is used for both encryption and decryption of data.

Private is kept secure or privately while the public key is given to the public, which is used for encryption of data. It is used for both encryption and decryption of data.

The message can be cracked by using the private key only. Therefore it is very important to not share the private key with anyone as it can leak the data.

Advantages of RSA:

1. RSA has proven to be stronger than any other algorithm used for a similar purpose.
2. It has overcome the main limitation of the symmetric algorithm of authenticity and confidentiality.
3. It is the most trusted algorithm.
4. Unlike DSA, it can do the decryption too.

Disadvantages of RSA:

The computation process is a time-consuming and lengthy one.

Therefore it is concluded that RSA is the best algorithm so far as it has fewer disadvantages and several advantages. It is used worldwide for encryption and decryption of data as no third party without the private key will be able to decrypt it.

What is DSA?

Several algorithms were made to make the digital signature as it is very important to make sure that the data is transmitted securely. These algorithms follow a similar method of private keys.

Therefore DSA was developed, which is used to create the digital signature. It cannot be used for encryption like RSA but only for generating and verifying the digital signature. Public or private keys are the basis for the signature generated with DSA.

The private key is the one with the person who generates the signature, and the public key is the one with the person who encrypts it. Private is very vital as it can be used for generating the same signature as yours.

Advantages of DSA:

1. It has very strong strength levels.
2. It also has small digital signature standards.
3. The speed of signature computation is very less.
4. It does not require large space as compared to others.
5. It does not include any charges and can be used for free.

Disadvantages of DSA:

1. The authentication process is very time-consuming as verification takes a lot of time.
2. The authentication of data can be done in DSA. It cannot be encrypted.
3. DSA is dependent on SHA1 has. Therefore, any limitation or problem of this is the problem reflected in DSA.

Main Differences Between RSA and DSA

1. Both RSA and DSA have separate uses. RSA is used for secure the data transmission while DSA has use of digital signature and also verification of it.
2. DSA was developed later in 1991 by the National Institutes of Standards and Technology than RSA, which was developed earlier in 1977 by Ron Rivest, Adi Shamir, and Leonard Adleman.
3. Both of them use a different concept of working. DSA uses discrete logarithm and modular exponentiation, while RSA uses the mathematical concept of two large prime factorizations.
4. RSA is best suited when it comes to encryption and verification, while DSA is for signing and decryption.
5. Both of them various benefits over each other, as RSA is slower in a key generation when compared to DSA, which is a lot faster for this, but when it comes to encryption, it’s totally opposite, RSA is faster than DSA in the encryption process.
6. Last but not least, DSA, being best suited for decryption, is faster in the process than the RSA.

References

1. https://ieeexplore.ieee.org/abstract/document/1056264/
2. https://link.springer.com/chapter/10.1007/3-540-68697-5_9
3. https://www.ams.org/notices/199902/boneh.pdf
4. https://link.springer.com/chapter/10.1007/978-3-540-28632-5_9
5. https://pubs.rsna.org/doi/abs/10.1148/radiol.2302021465
6. https://www.sciencedirect.com/science/article/pii/S0013468600003388