Showing papers on "Password published in 1981"

Password authentication with insecure communication

Abstract: A method of user password authentication is described which is secure even if an intruder can read the system's data, and can tamper with or eavesdrop on the communication between the user and the system. The method assumes a secure one-way encryption function and can be implemented with a microcomputer in the user's terminal.

Protection system for intelligent cards

Abstract: There is disclosed a protection system for intelligent cards. Each card has stored in it a code which is the encryption of a concatenation of a user secret password and a common reference text. The encryption is derived by an initialization terminal which uses the private key associated with the public key of a public-key cryptosystem key pair. Each transaction terminal with which a card is used decrypts the stored code in accordance with the public key. A transaction is effected only if the stored code decrypts into the user password which is inputted on a keyboard and the common reference text.

Cryptographic Authentication of Time-Invariant Quantities

Abstract: With any strong cryptographic algorithm, such as the data encryption standard (DES), it is possible to devise protocols for authentication. One technique, which allows arbitrary, time-invariant quantities (such as encrypted keys and passwords) to be authenticated, is based upon a secret cryptographic (master) key residing in a host processor. Each quantity to be authenticated has a corresponding precomputed test pattern. At any later time, the test pattern can be used together with the quantity to be authenticated to generate a nonsecret verification pattern. The verification pattern can in turn be used as the basis for accepting or rejecting the quantity to be authenticated.

A Password Extension for Improved Human Factors.

Abstract: To maximize both the difficulty of guessing passwords and also the ease of remembering passwords, we use a fairly large keyspace (64 bits) and a very long “passphrase” (up to 80 characters) The phrase is hashed into the key, which is then stored in encrypted form The hashing necessarily includes one-way encryption Since the phrase is long, one would expect a large keyspace for the actual phrase as well as for the hashed phrase Since the phrase is meaningful to the owner it should be easier to remember

Voice recognizing telephone call denial system

Abstract: A call denial apparatus for denying a subscriber's access to a trunk. A voice recognizer is connected to the trunk, and receives a password spoken by the subscriber. The apparatus then receives digits dialed by the subscriber over the subscriber's line and carried by the trunk, matching them with one or a series of digits stored in a memory. In the event the password or subscriber's voice matches a predetermined password or voice, the digits which are dialed are passed over the trunk. However in the event that the password or voice does not match the predetermined password or voice, and in the event a predetermined one or group of digits are dialed which match a prohibited digit or group of digits stored in the memory, the trunk is split, and the subscriber is restricted from further access to the trunk. Thus only predetermined subscribers have full access to the trunk, and other subscribers have access only for limited services, or for no services. The voice recognition design allows different subscribers to have different classes of service, and for the first time does not tie trunk restriction to a subscriber's line, but to an actual subscriber.

Integrating the Data Encryption Standard into Computer Networks

Abstract: The NBS Data Encryption Standard may be integrated into computer networks to protect personal (nonshared) files, to communicate securely both on- and off-line with local and remote users, to protect against key substitution, to authenticate system users, to authenticate data, and to provide digital signatures using a nonpublic key encryption algorithm. Key notarization facilities give users the capability of exercising a set of commands for key management as well as for data encryption functions. The facilities perform notarization which, upon encryption, seals a key or password with the identities of the transmitter and intended receiver. Thus, in order to decrypt a message, the receiver must authenticate himself and supply the correct identity of the transmitter. This feature eliminates the threat of key substitution which must be protected against to attain a high level of security.