Abstract: A system for protecting information over the Internet, or other public network, is provided at a web site addressable by one or more client computer systems. Each client computer system connects to the web site to receive a respondent identifier and viewer software. When the viewer software is installed at the client computer system, it generates a unique viewer identifier identifying the client computer system. The viewer identifier is sent to the web site for registering the viewer identifier with the respondent identifier. The web site has a database and one or more web servers coupled to the database. The database stores registration information including the viewer identifier and associated respondent identifiers for the client computer systems, encrypted content information files and keys to decrypt such files, survey invitation information for each of the surveys, and exposure limit information. The client computer system receives an E-mail invitation to participate in a survey.

Abstract: A system at a web site addressable by one or more client computers. Each client computer connects to the web site to receive a respondent identifier and a viewer. The viewer at the client computer generates a unique viewer identifier identifying the client computer, and sends that identifier to the web site for registration with the respondent identifier. The viewer connects to the web site and downloads a file with encrypted content information. The viewer requests the web site for a key to decrypt the file. Based on the respondent and viewer identifiers, and the particular survey and exposure limits, a key is sent to the client computer. The viewer decrypts the encrypted file with the key, and then shows the content information in a window. During viewing, the viewer ignores interrupts from the computer's user interface enabling copying, and stops showing the decrypted content if another window is selected.