Aryabhata, an ancient Indian mathematician and astronomer, is credited with developing the first known cryptographic techniques in the 5th century AD.

S. S. Shrikhande, an Indian mathematician, is known for his work in coding theory, particularly in the design of error-correcting codes.

Claude Shannon, an American mathematician and engineer, is widely regarded as the father of information theory. His work, including the Shannon-Hartley theorem, laid the foundation for modern communication systems.

Adi Shamir, an Israeli mathematician and computer scientist of Indian origin, is known for his contributions to cryptography, including the development of the RSA algorithm along with Ron Rivest and Leonard Adleman.

Alan Turing, a British mathematician and computer scientist, is widely recognized as one of the pioneers of modern cryptography. His work during World War II on breaking the German Enigma code played a crucial role in the Allied victory.

R. Ahlswede, a German mathematician of Indian origin, is known for his work in network coding theory, particularly for introducing the concept of network information flow.

Richard Hamming, an American mathematician, is known for his work on error-correcting codes, including the development of the Hamming code, which is widely used in digital communication systems.

V. D. Goppa, an Indian mathematician, is known for his work in algebraic coding theory, particularly for developing the Goppa codes, which are used in various communication systems.

Claude Shannon, an American mathematician and engineer, is widely regarded as the father of information theory. His work, including the noisy-channel coding theorem, laid the foundation for modern communication systems.

A. D. Wyner, an American mathematician of Indian origin, is known for his work on the theory of information and coding, particularly for developing the Wyner-Ziv theorem, which deals with the problem of data compression in the presence of noise.

Whitfield Diffie, an American mathematician and cryptographer, is known for his contributions to cryptography, including the development of the Diffie-Hellman key exchange protocol along with Martin Hellman.

Irving S. Reed, an American mathematician of Indian origin, is known for his work on the theory of error-correcting codes, particularly for developing the Reed-Solomon codes, which are widely used in various communication systems.

Claude Shannon, an American mathematician and engineer, is widely regarded as the father of information theory. His work, including the development of the Shannon entropy, laid the foundation for modern communication systems.

David Slepian, an American mathematician of Indian origin, is known for his work on the theory of information and coding, particularly for developing the Slepian-Wolf theorem, which deals with the problem of data compression in the presence of side information.

Taher ElGamal, an Egyptian cryptographer, is known for his contributions to cryptography, including the development of the ElGamal encryption scheme, which is widely used in various cryptographic applications.