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    11.
    发明专利
    未知

    公开(公告)号：DE68926005T2

    公开(公告)日：1996-10-17

    申请号：DE68926005

    申请日：1989-08-09

    Applicant: IBM

    Inventor： MATYAS STEPHEN M ,  ABRAHAM DENNIS G ,  JOHNSON DONALD B ,  KARNE RAMESH K ,  LE AN V ,  PRYMAK ROSTISLAW ,  THOMAS JULIAN ,  WILKINS JOHN D ,  YEH PHIL C ,  SMITH RONALD M ,  WHITE STEVE R ,  ARNOLD WILLIAM C

    IPC: G07F7/10 ,  H04L9/00 ,  H04L9/08 ,  H04L9/32

    Abstract: Arrangements are disclosed for validating that key management functions requested for a cryptographic key by the program have been authorised by the originator of the key. The invention includes a cryptographic facility characterised by a secure boundary through which passes an input path for receiving the cryptographic service requests, cryptographic keys and their associated control vectors, and an output path for providing responses thereto. There can be included within the boundary a cryptographic instruction storage coupled to the input path, a control vector checking unit and a cryptographic processing unit coupled to the instruction storage, and a master key storage coupled to the processing means, for providing a secure location for executing key management functions in response to the received service requests. The cryptographic instruction storage receives over the input path a cryptographic service request for performing a key management function on a cryptographic key. The control vector checking unit has an input coupled to the input path for receiving a control vector associated with the cryptographic key and an input connected to the cryptographic instruction storage, for receiving control signals to initiate checking that the control vector authorises the key management function which is requested by the cryptographic service request. The control vector checking unit has an authorisation output connected to an input of the cryptographic processing means, for signalling that the key management function is authorised, the receipt of which by the cryptographic processing unit initiates the performance of the requested key management function with the cryptographic key. The invention enables the flexible control of many cryptographic key management functions in the generation, distribution and use of cryptographic keys, while maintaining a high security standard.

    SECURE MANAGEMENT OF KEYS USING CONTROL VECTORS WITH MULTI-PATH CHECKING
    14.
    发明专利
    SECURE MANAGEMENT OF KEYS USING CONTROL VECTORS WITH MULTI-PATH CHECKING 未知

    公开(公告)号：CA2007409C

    公开(公告)日：1998-10-06

    申请号：CA2007409

    申请日：1990-01-09

    Applicant: IBM

    Inventor： MATYAS STEPHEN M ,  ABRAHAM DENNIS G ,  JOHNSON DONALD B ,  KARNE RAMESH K ,  PRYMAK ROSTISLAW ,  WILKINS JOHN D ,  MCCORMACK PATRICK J ,  LE AN V

    IPC: G06F9/00 ,  G06F9/46

    Abstract: An apparatus and method are disclosed for validating that a cryptographic function requested to be performed with a cryptographic key has been authorized by the originator of the key. The invention is used in a data processing system which processes cryptographic service requests for the performance of cryptographic functions with cryptographic keys which are associated with control vectors defining the functions which each key is allowed by its originator to perform. The invention includes a cryptographic facility characterized by a secure boundary through which passes an I/O path for receiving a cryptographic key and its associated control vector, and for providing a response thereto, there being included within the boundary a cryptographic processing means coupled to the I/O path and a master key storage coupled to the processing means, for providing a secure location to execute a cryptographic function with the cryptographic key. In accordance with the invention, a first control vector checking means has an input to receive at least a first portion of the associated control vector and to receive a cryptographic service request to perform the cryptographic function with the cryptographic key, for performing a first check of the first portion of the associated control vector to determine if the cryptographic function is authorized to be performed by the cryptographic key. The first control vector checking means has a first authorization output coupled to the cryptographic processing means, for outputting a first authorization signal that the cryptographic function is authorized to be performed by the cryptographic key. Further in accordance with the invention, a second control vector checking means has an input to receive at least a second portion of the associated control vector and to receive a cryptographic service request to perform the cryptographic function with the cryptographic key, for performing a second check of the second portion of the associated control vector to determine if the cryptographic function is authorized to be performed by the cryptographic key. The second control vector checking means has a second authorization output coupled to the cryptographic processing means, for outputting a second authorization signal that the cryptographic function is authorized to be performed by the cryptographic key. The cryptographic processing means initiates the execution of the cryptographic function with the cryptographic key in response to receiving the first and second authorization signals. In this manner, distributed control vector checking operations are enabled for multiprocessing, remote terminal, smart card and multiprogramming applications.

    TWO-SPEED BI-DIRECTIONAL, CLOSED LOOP STEPPER MOTOR CONTROL CIRCUIT
    17.
    发明专利
    TWO-SPEED BI-DIRECTIONAL, CLOSED LOOP STEPPER MOTOR CONTROL CIRCUIT 未知

    公开(公告)号：CA960296A

    公开(公告)日：1974-12-31

    申请号：CA110071

    申请日：1971-04-13

    Applicant: IBM

    Inventor： ABRAHAM DENNIS G

    IPC: G05D3/18

    Abstract: 1288198 Controlling motors INTERNATIONAL BUSINESS MACHINES CORP 19 April 1971 [22 April 1970] 27185/71 Heading H2J A stepping motor may be rotated continuously in either direction at a low or high speed by a control system comprising a single feedback encoder driven by the motor and supplying feedback pulses in accordance with the motor speed, a bi-directional sequencer supplying motor control pulses for sequentially energizing the windings of the motor, direction control means for reversing the sequence of the motor control pulses to reverse the motor direction, means for starting the motor, running it at high or low speeds and for changing from one speed to another, and a deceleration means for retarding the motor field to stop the motor. To start the motor and accelerate to low speed, a command signal on line RL sets on a run trigger RL which fires a single shot 5 via an OR circuit 7 to the sequencer BDC which displaces the motor field and causes the rotor of the motor to move in accordance with the displaced field; the feedback encoder supplies pulses along line FBL to an AND circuit 9 and a single shot 13 which sends pulses to the OR circuit 7 to displace the motor field: the motor thus accelerates to saturation speed. To start the motor and accelerate it to the high speed a command signal on line RHSL causes triggers TR-1 and TR-2 to be set on, TR-2 firing a single shot 19 to supply an extra pulse to the sequencer which causes the motor field to move to an advanced position which has the effect of changing the lead angle of the feedback encoder by one motor slip causing acceleration to the high speed. Change from low to high speed involves the extra pulse referred to in the acceleration to high speed and produced when desired by energization of the line RHSL. Change from high to low speed is accomplished by de-energizing RHSL to reset TR-1 whose output blocks the next feedback pulse to the OR circuit 7 and the motor driving circuits; the next feedback pulse resets TR-2, blocks AND 12 and allows single shot 13 to send a pulse to advance the sequencer and return it to its normal position for low speed. Stopping the motor is accomplished by bringing the field to a position where it lags the rotor and generates negative torque: de-energization of the RL line resets trigger RTR to cause a stopping sequence generator 21 to send pulses to the OR circuit and sequencer to displace the motor field to provide the lag, and when the feedback pulses have slowed sufficiently single shot 22 is fired to reset latch FL and fire single shot 21 which delivers a damping pulse to the sequencer to provide a smooth stop.

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