An D Le

US Patent:

51777916, Jan 5, 1993

Filed:

Aug 30, 1991

Appl. No.:

7/753245

Inventors:

Phil C. Yeh - Poughkeepsie NY
Dennis G. Abraham - Concord NC
Donald B. Johnson - Manassas VA
An Van Le - Manassas VA
Stephen M. Matyas - Manassas VA
Ronald M. Smith - Wappingers Falls NY
John D. Wilkins - Somerville VA

Assignee:

International Business Machines Corp. - Armonk NY

International Classification:

H04L 932

US Classification:

380 45

Abstract:

A working key of a certain key type is to be transmitted from a first system (having a first usage-control value associated with keys of the certain type) and a second system (having a second usage-control value associated with keys of the certain type). A translation control value, associated with the certain key type, is generated, functionally relating the first and second usage-control values. The translation control value is used in a cryptographic function to send or receive the working key between systems, the cryptographic function being designed to produce valid results when the correct translation control value, and usage-control values, are employed, and unpredictable results otherwise. Effectively, the first usage-control value is translated to the second usage-control value.

US Patent:

52146987, May 25, 1993

Filed:

Mar 20, 1991

Appl. No.:

7/672265

Inventors:

Ronald M. Smith - Wappingers Falls NY
Phil C. Yeh - Poughkeepsie NY
Randall J. Easter - Poughkeepsie NY
Donald B. Johnson - Manassas VA
An Van Le - Manassas VA
Stephen M. Matyas - Manassas VA
Julian Thomas - Poughkeepsie NY
John D. Wilkins - Somerville VA

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

H04L 908

US Classification:

380 21

Abstract:

A cryptographic facility implements a multiple key part import procedure. The installation manager can verify that a key part has been correctly entered and has not been compromised. The security requirement for the procedure is that no single party can subvert the system security by misusing the procedure. This is accomplished by the use of a control-vector-dependent verification pattern to indicate that each key part has been accepted by using the proper control vector and the use of different key switch positions to specify whether the key part is a master key part or an operational key part and whether the key part is a first part or a subsequent key part. The apparatus provides an automatic reset of the key part register at the completion of each key-entry instruction so that each key part can be imported only once. This prevents the same key part from being imported twice as different key part types. The apparatus also prevents a key part from being combined with itself to create a known key.