Digital signal processing techniques and architectures in secure facsimile communications

A flexible Digital Signal Processing (DSP) oriented approach for implementing secure facsimile (fax) communications systems is presented. The signal processing techniques for fax coding, data encryption, and automatic cryptographic key management based on Public Key cryptography are discussed. The proposed system architecture can exploit the latest advances in DSP microprocessor technology to offer lower cost, reduced size, and higher performance cryptosystems. This approach was successfully adopted by Intracom S.A. in the design and implementation of the Secline-Fax secure fax communications system.