Michael O. Rabin had important contributions in many domains, but from a practical point of view the most important are his contributions to cryptography.
After Ralph Merkle, Whitfield Diffie and Martin Hellman, Michael O. Rabin is the most important of the creators of public-key cryptography.
The RSA team (Ron Rivest, Adi Shamir and Leonard Adleman) is better known than Michael O. Rabin, but that is entirely due to marketing and advertising, because they founded a successful business.
In reality the RSA algorithm is superfluous and suboptimal. If the RSA team had never discovered this algorithm, that would have had a null impact on the practice of cryptography. Public-key cryptography would have been developed equally well, because the algorithms discovered by Merkle, Diffie, Hellman and Rabin are necessary and sufficient.
On the other hand, while without the publications of RSA, cryptography would have evolved pretty much in the same way, without the publications of Michael O. Rabin from the late seventies the development of public-key cryptography would have been delayed by some years, until someone else would have made the same discoveries.
Together with Ralph Merkle, Michael O. Rabin was the one who discovered the need for secure cryptographic hash functions, i.e. one-way hash functions, which are now critical for many applications, including digital signatures.
Originally, Merkle defined 2 conditions for one-way hash functions, of resistance to first preimage attacks and second preimage attacks, while Rabin defined 1 condition, of resistance to collision attacks. Soon after that it was realized that all 3 conditions are mandatory, so the 2 definitions, of Merkle and of Rabin, have been merged into the modern definition of such hash functions.
Unfortunately, both Merkle and Rabin have overlooked a 4th condition, of resistance to length extension attacks. This should have always be included in the definition of secure hash functions.
Because this 4th condition was omitted, the US Secure Hash Algorithm Standards defined algorithms that lack this property, which has forced many applications to use workarounds, like the HMAC algorithm, which for many years have wasted time and energy wherever encrypted communications were used, until more efficient authentication methods have been standardized, like GCM, which is the most frequently used algorithm today.
Michael O. Rabin had important contributions in many domains, but from a practical point of view the most important are his contributions to cryptography.
After Ralph Merkle, Whitfield Diffie and Martin Hellman, Michael O. Rabin is the most important of the creators of public-key cryptography.
The RSA team (Ron Rivest, Adi Shamir and Leonard Adleman) is better known than Michael O. Rabin, but that is entirely due to marketing and advertising, because they founded a successful business.
In reality the RSA algorithm is superfluous and suboptimal. If the RSA team had never discovered this algorithm, that would have had a null impact on the practice of cryptography. Public-key cryptography would have been developed equally well, because the algorithms discovered by Merkle, Diffie, Hellman and Rabin are necessary and sufficient.
On the other hand, while without the publications of RSA, cryptography would have evolved pretty much in the same way, without the publications of Michael O. Rabin from the late seventies the development of public-key cryptography would have been delayed by some years, until someone else would have made the same discoveries.
Together with Ralph Merkle, Michael O. Rabin was the one who discovered the need for secure cryptographic hash functions, i.e. one-way hash functions, which are now critical for many applications, including digital signatures.
Originally, Merkle defined 2 conditions for one-way hash functions, of resistance to first preimage attacks and second preimage attacks, while Rabin defined 1 condition, of resistance to collision attacks. Soon after that it was realized that all 3 conditions are mandatory, so the 2 definitions, of Merkle and of Rabin, have been merged into the modern definition of such hash functions.
Unfortunately, both Merkle and Rabin have overlooked a 4th condition, of resistance to length extension attacks. This should have always be included in the definition of secure hash functions.
Because this 4th condition was omitted, the US Secure Hash Algorithm Standards defined algorithms that lack this property, which has forced many applications to use workarounds, like the HMAC algorithm, which for many years have wasted time and energy wherever encrypted communications were used, until more efficient authentication methods have been standardized, like GCM, which is the most frequently used algorithm today.