Question

State (in your own words) the justification for having this alternate mechanism when RSA is already well established. Consider the security and the computational aspects of the schemes. Be as specific as possible.

Answer 1

Rivest-Shamir-Adleman known as RSA is a algorithm most populary used for crypotoanalysis. On the basis of current usage of algorithms for crypotoanalysis RSA is the most powerful and secured since it is hard to break.

But although the RSA algorithm is already well established having a high computational complexity, and impossible for today's computer systems to break the keys present in RSA, there are also some alternate mechanism established in case of the failure of RSA.

This is because it has been said that a practical quantum computer will be able to break the RSA algorithm encryption and digital signatures. so, for the post - quantum cryptography several alternates mechanism are made one of those is Learning with Errors scheme (LWE) which is a lattice based cryptography system. It also includes other algorithms such as code- based encryption etc.

In consideration of the security, the RSA algorithm is secured for the present-day computers but while considering the quantum computers the security for encrypted data is not secured in RSA but on the other hand, The lattice cryptography (LWE) is secured in quantum computers. The RSA algorithms are secured and are also hard to break with high computational complexity.

Hence, for now the RSA algorithm is the powerful and secured algorithm but when the use of quantum computers is more frequent than we have to go for other encryption algorithms.