Abstract: A method for securely storing analog or digital data on a data storage medium. An analog information signal is combined with a noise signal. The composite noise and information signal is encrypted with a key which is derived from the noise signal. The encrypted composite signal is compressed and then recorded on the data storage medium along with an encrypted value of the key. The storage medium data is read, decompressed, and decrypted using a decryption key derived from the stored encrypted key. The data is then converted to an analog signal and combined with a noise correction signal derived from said key to eliminate the noise signal added to the analog information signal before storing the signal on the data storage medium.

Abstract: A self contained data medium is provided with an apparatus for generating a decrypting key for decrypting stored data. Frames of encrypted data are stored on the data medium such as a video or audio disk. Each frame of data includes a header which has a frame identification number. A reader reads each frame of data including the header with the frame identification number. The reader transmits the frame number to a transponder attached to the data medium. The transponder includes a decryption engine which calculates a decryption key from the frame number and a secret deciphering key stored in the transponder. The transponder transmits the decryption key to the reader which uses the decryption key to decrypt the frame of data. The system discourages both home copying and commercial piracy of the underlying program material.

Abstract: A method and system for secure distribution of protected data using elliptic curve systems includes a program to unlock software. The user obtains an encrypted unlocking code from a processing center and enters it into the unlocking program, which decrypts the message, yielding the unlocking code, then uses the unlocking code to unlock the software. To encrypt the unlocking code, the processing center selects an appropriate unlocking code using information received from the user, selects an elliptic curve to use, selects a first point on the elliptic curve having an index corresponding to the information to be encrypted, generates a delta key and a center key and the finite field inverse of the center key, selects a second point on the elliptic curve which is the product of the inverse of the center key and the first point, and generates an index of the second point, which, with the delta key, is the encrypted information.

Abstract: Communication between a plurality of computers which are intercoupled or networked is provided in confidential form using password protection in combination with a special hardware token which is used to generate a one-time random session ciphering key.

Abstract: A developer writing a software program provides security for the program being prepared by interposing a special security layer in front of the standard library being utilized for writing the program. A security header and security file are incorporated in the software which automatically reroutes standard library calls through the special security layer prior to putting the calls through to the standard library files.

Abstract: In order to provide office security for receiving facsimile transmissions, a particular key or password of a receiver of a transmission is sent to the sender. The sender of a facsimile message incorporates the graphic pattern of the key of the receiver in a predetermined location on the first page of the facsimile message which is intercepted at the receiving end by a security reader which looks for the key. If the key is present, the message is placed in storage where it may be retrieved by the receiver by simply keyboarding the password related to the key to retrieve the stored message. If the key is not present, the facsimile transmission is sent on to a standard facsimile machine of the receiver.

Abstract: A method is provided for protecting distributed software which relies on a unique factor such as an accessible serial number or the generation of a profile or fingerprint of the computer of the user which is entered individually and/or with a random factor to generate a unique first key which will differ for different computers. The first key is sent to a processing center which then generates a second key. The user applies the second key which compares the unique and/or random factors. If the comparison matches, the first and second keys are used in an algorithm in the software to generate a decrypting key permitting the customer to purchase the selected program(s).