Abstract: An improved security system is disclosed which uses an IC card to enhance the security functions involving component authentication, user verification, user authorization and access control, protection of message secrecy and integrity, management of cryptographic keys, and auditability. Both the security method and the apparatus for embodying these functions across a total system or network using a common cryptographic architecture are disclosed. Authorization to perform these functions in the various security component device nodes in the network can be distributed to the various nodes at which they will be executed in order to personalize the use of the components.

Abstract: An improved security system is disclosed which uses an IC card to enchance the security functions involving component authentication, user verification, user authorization and access control, protection of message secrecy and integrity, management of cryptographic keys, and auditablity. Both the security method and the apparatus for embodying these functions across a total system or network using a common cryptographic architecture are disclosed. Authorization to perform there functions in the various security component device nodes in the network can be distributed to the various nodes at which they will be executed in order to personalize the use of the components.

Abstract: A system for authenticating components in a communications system using cryptographic techniques to determine if each has the proper key without disclosing information which would be useful to an imposter in deriving the key. A random number generated at a first terminal is encrypted under its key for transmission as a first value to a second terminal whose identity is to be authenticated. The second terminal decrypts the transmitted first value using its key deriving a second value (which equals the random number if the keys are identical.) The second terminal then encrypts its key using the second value as the key, generating a third value which is transmitted back to the first terminal for verification. The first terminal then verifies the third value, either by decrypting it using the random number as the key to obtain its key or by encrypting its key using the random number as key to derive the third number (if the two keys are identical.