Coded Modulation and the Arrival of Signcryption

Digital communications engineers strive to transmit data in a more efficient and reliable manner, while cryptographers endeavor to offer both data confidentiality and integrity. In the 1970's and 1980's, researchers in digital communications successfully developed techniques for multi-level coded modulation that simultaneously allow the correct of transmissions errors and the demodulation of signals upon the arrival at the receiver. Reminiscent of coded modulation, signcryption is a cryptographic technique developed to "hit two birds in one stone", namely to provide both data confidentiality and origin unforgeability with reduced overhead. In this article the author recounts his unique experience in witnessing the evolution and perfection of coded modulation techniques, and more important, how the experience inspired him to embark on the journey of searching for efficient techniques for combining public key encryption and digital signatures; the author also attempts to illuminate future directions for efficient, hybrid cryptographic techniques.