MOSTAFA HASHEM SHERIF, PhD, is a Certified Project Manager and internationally recognized as an expert on standards for packetized voice and digital signal processing in transmission equipment. He currently is a Senior Technical Specialist for AT&T and is the recipient of the AT&T Standards Recognition Award. Dr. Sherif holds several U.S. patents and is the Standards coeditor for IEEE Communications Magazine and the author of the bestselling book Protocols for Secure Electronic Commerce.