International Business Machines Corporation

Gene Y Tsudik

Philippe A Janson

Mohammad Peyravian

Stephen M Matyas

James P Gray

Mark Holmes Linehan

Elsie A Van Herreweghen

Refik Molva

Ralf Ch Hauser

Nicholas J Simicich

A robust and secure password (or key) change method between a user and an authentication server in a distributed communication network is disclosed. The protocol requires the exchange of only two messages between the user desiring the key change and the server, the user's request including, at least partly encrypted, an identification of the sending user, old and new keys, and two nonces, at least one including a time indication. The authentication server's response includes a possibly encrypted accept/reject indication and the regularly encrypted request from the user.

Method and system for changing an authorization password or key in a

Method and system for providing secure key distribution in a

The security provided by encryption of ATM cells is enhanced by testing each cell for low data content level. If a cell has a low data content, its contents are nevertheless compressed and the resulting string is used to replace the original data. A length character and a randomly generated number which are added to the freed-up byte positions in the data field of the cell. The entire, modified data field is encrypted before the cell is transmitted. At a receiving system, a compression indicator is checked to determine whether the cell contains original or compressed data. If necessary, the length field and the random number are stripped and the remaining cell data is decompressed before the cell data is decrypted.

Encryption of low data content ATM cells

A computing system is described having an automated management system for managing keys to encrypt and decrypt stored data on the computing system. The computing system has an authentication server; a key client; a key generator; a key server; a key database; and an encrypted data file memory. The authentication server authenticates the user and in response to the user accessing the computing system the authentication server provides the user with a ticket validating the user. The key client of a creating user when creating a data file invokes the generator to generate a key corresponding to the data file. The key is provided to the key server and the key client uses the key to encrypt the data file which is stored in the encrypted data file memory. The key client of an accessing user sends its ticket and data file identification data to the key server. The key server checks the ticket and sends the key corresponding to the data file to the key client of the accessing user. The key client of the accessing user uses the key to decrypt the encrypted data file. The stored data can further include a header containing the key and owner and permitted user identification data. The ticket can contain a key to encrypt messages sent between the client server and key client.

Personal key archive

Growing community of inventors

Thalwil, Switzerland

Gene Y Tsudik