Abstract: A secure method for sending register, authenticated electronic documents is disclosed. The sender sends a first set of data, not including the plaintext message, encrypted with the public key of the recipient, and a second set of data, including the plaintext message, encrypted with a session key which was included in the encrypted first set of data. The recipient is first asked if he wants to receive the message, and then, upon seeing an abstract, asked if he wants to receive the full message. Confirmatory data regarding the decryption of the message and the presentation of the data to the recipient is recorded and sent to an authentication agent.

Abstract: A portable Personal Identification Card allows a cardholder to enter a PIN code into his card at a location remote from an authorization terminal. In an alternate embodiment, a PIN code may be entered at the authorization terminal. The authorization terminal reads the cardholder's account number from the PIN card. The account number is transmitted to a central computer which uses this number to index into memory to find a personal identification number and encryption parameters. The central computer transmits a pseudo-random number to the PIN Card. Both the PIN Card and the central computer perform an encryption of a function of the corresponding personal identification number and pseudo-random number to derive a CGIPIN (Computer Generated Image of the PIN). If the CGIPIN transmitted from the PIN card matches the CGIPIN of the central computer, access is authorized.

Abstract: A portable Personal Identification Card allows a cardholder to enter a PIN code into his card at a location remote from an authorization terminal. In an alternate embodiment, a PIN code may be enterd at the authorization terminal. The authorization terminal reads the cardholder's account number from the PIN card. The account number is transmitted to a central computer which uses this number to index into memory to find a personal identification number and encryption parameters. The centerl computer transmits a pseudo-random number to the PIN Card. Both the PIN Card and the central computer perform an encryption of a function of the corresponding personal indentification number and pseudo-random number to derive a CGIPIN (Computer Generated Image of the PIN). If the CGIPIN transmitted from the PIN card matches the CGIPIN of the central computer, access is authorized.

Abstract: A pet watch process and circuit discloses the use of an animal carried timer that gives audio signal after a preset time has elapsed. The timer is used in conjunction with a conditioning program to produce a desired motive behavior, e.g., to induce an animal to come home when the audio signal sounds. The timer is incremently adjustable and has a liquid crystal display. The conditioning method is an incremental process which begins with the owner calling the pet and sounding the alarm simultaneously with the pet in the same room, after longer and longer incremental time intervals, and finally is set off with the pet remote from its owner. (i.e. outside the house) As the training process proceeds, the alarm is set off.