CONTENTS

�1���� Introduction
�2���� Electronic messaging
������� 2.1���� Operational characteristics
������� 2.2���� General description
�3���� Interactive Internet and Intranet applications
������� 3.1���� Operational characteristics
������� 3.2���� General description
�4���� File transfer
������� 4.1���� Operational characteristics
������� 4.2���� General description
5���� Digital voice
������� 5.1���� Operational characteristics
������� 5.2���� General description
�6���� Software defined radio
������� 6.1���� Operational characteristics
������� 6.2���� General description