Abstract: The invention provides a method of securing remote terminal access to a central computer. The method uses the services of a physically secure coprocessor which is, or will be, coupled to the remote terminal for the purposes of effecting remote access to the central computer. The method comprises transferring an encrypted decryption key from the central computer to the physically secure coprocessor. The coupling between the coprocessor and remote terminal allows a file to be encrypted which can confirm that the remote terminal (which is the source of the encrypted file) has or had access to the specific coprocessor to which the encrypted decryption key had previously been transferred. Thereafter the encrypted file is transferred to the central computer and is examined there to confirm that the source of the file has access to the specific coprocessor which received the encrypted decryption key.

Abstract: Method and apparatus which restricts software, distributed on magnetic media, to use on a single computing machine. The original medium is functionally uncopyable, until it is modified by the execution of a program stored in a tamper proof co-processor which forms a part of the computing machine. The modified software on the original medium may then be copied, but the copy is operable only on the computing machine containing the co-processor that performed the modification.

Abstract: Method and apparatus which restricts software, distributed on magnetic media, to use on a single computing machine. The original medium is functionally uncopyable, until it is modified by the execution of a program stored in a tamper proof co-processor which forms a part of the computing machine. The modified software on the original medium may then be copied, but the copy is operable only on the computing machine containing the co-processor that performed the modification.