Patents by Inventor Toshio Tokita

Toshio Tokita has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7864950
    Abstract: It is desired to share one circuit by an encryption unit 200 and a decryption unit 500. A normal data transformation unit (FL) 251 and an inverse data transformation unit (FL?1) 273 are located at point symmetry on a non-linear data transformation unit 220, and a normal data transformation unit (FL) 253 and an inverse data transformation unit (FL?1) 271 are located at point symmetry on the non-linear data transformation unit 220. Therefore, the encryption unit 200 and the decryption unit 500 can be configured using the same circuits.
    Type: Grant
    Filed: March 8, 2001
    Date of Patent: January 4, 2011
    Assignees: Mitsubishi Denki Kabushiki Kaisha, Nippon Telegraph and Telephone Corporation
    Inventors: Mitsuru Matsui, Toshio Tokita, Junko Nakajima, Masayuki Kanda, Shiho Moriai, Kazumaro Aoki
  • Patent number: 7822196
    Abstract: It is desired to share one circuit by an encryption unit 200 and a decryption unit 500. A normal data transformation unit (FL) 251 and an inverse data transformation unit (FL?1) 273 are located at point symmetry on a non-linear data transformation unit 220, and a normal data transformation unit (FL) 253 and an inverse data transformation unit (FL?1) 271 are located at point symmetry on the non-linear data transformation unit 220. Therefore, the encryption unit 200 and the decryption unit 500 can be configured using the same circuits.
    Type: Grant
    Filed: October 28, 2005
    Date of Patent: October 26, 2010
    Assignees: Mitsubishi Denki Kabushiki Kaisha, Nippon Telegraph and Telephone Corporation
    Inventors: Mitsuru Matsui, Toshio Tokita, Junko Nakajima, Masayuki Kanda, Shiho Moriai, Kazumaro Aoki
  • Patent number: 7760870
    Abstract: It is desired to share one circuit by an encryption unit 200 and a decryption unit 500. A normal data transformation unit (FL) 251 and an inverse data transformation unit (FL?1) 273 are located at point symmetry on a non-linear data transformation unit 220, and a normal data transformation unit (FL) 253 and an inverse data transformation unit (FL?1) 271 are located at point symmetry on the non-linear data transformation unit 220. Therefore, the encryption unit 200 and the decryption unit 500 can be configured using the same circuits.
    Type: Grant
    Filed: October 28, 2005
    Date of Patent: July 20, 2010
    Assignees: Mitsubishi Denki Kabushiki Kaisha, Nippon Telegraph and Telephone Corporation
    Inventors: Mitsuru Matsui, Toshio Tokita, Junko Nakajima, Masayuki Kanda, Shiho Moriai, Kazumaro Aoki
  • Patent number: 7760871
    Abstract: It is desired to share one circuit by an encryption unit 200 and a decryption unit 500. A normal data transformation unit (FL) 251 and an inverse data transformation unit (FL?1) 273 are located at point symmetry on a non-linear data transformation unit 220, and a normal data transformation unit (FL) 253 and an inverse data transformation unit (FL?1) 271 are located at point symmetry on the non-linear data transformation unit 220. Therefore, the encryption unit 200 and the decryption unit 500 can be configured using the same circuits.
    Type: Grant
    Filed: October 28, 2005
    Date of Patent: July 20, 2010
    Assignees: Mitsubishi Denki Kabushiki Kaisha, Nippon Telegraph and Telephone Corporation
    Inventors: Mitsuru Matsui, Toshio Tokita, Junko Nakajima, Masayuki Kanda, Shiho Moriai, Kazumaro Aoki
  • Patent number: 7697684
    Abstract: It is desired to share one circuit by an encryption unit 200 and a decryption unit 500. A normal data transformation unit (FL) 251 and an inverse data transformation unit (FL?1) 273 are located at point symmetry on a non-linear data transformation unit 220, and a normal data transformation unit (FL) 253 and an inverse data transformation unit (FL?1) 271 are located at point symmetry on the non-linear data transformation unit 220. Therefore, the encryption unit 200 and the decryption unit 500 can be configured using the same circuits.
    Type: Grant
    Filed: October 28, 2005
    Date of Patent: April 13, 2010
    Assignees: Mitsubishi Denki Kabushiki Kaisha, Nippon Telegraph and Telephone Corporation
    Inventors: Mitsuru Matsui, Toshio Tokita, Junko Nakajima, Masayuki Kanda, Shiho Moriai, Kazumaro Aoki
  • Patent number: 7184549
    Abstract: To encrypt another piece of data during encrypting process of a certain piece of data, a memory 55 is provided in parallel with a feedback line 65 which feeds back data from an encrypting module 51using an encryption key K to a selector 54. When an interrupt IT for processing plaintext block data N1 is generated while plaintext block data M1 is processed, ciphertext block data C1 at timing of generation of the interrupt IT is made to be stored in a register 56. The ciphertext block data C1 stored in the memory 55 is made to be selected by the selector 54 at timing of completion of processing the plaintext block data N1, and processing the plaintext block data M1+1 is started.
    Type: Grant
    Filed: December 22, 2000
    Date of Patent: February 27, 2007
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Toru Sorimachi, Toshio Tokita
  • Patent number: 7096369
    Abstract: In a data transformation apparatus for transforming two arbitrary pieces of data of A input data and B input data, a first nonlinear transformation of the A input data is performed using a first key parameter, a transformed result is output, an XOR operation of the transformed result and the B input data is performed to output an XORed result as B intermediate data, and the B intermediate data is input to a next sub-transformation unit as B input data. On the other hand, the B input data is input to a next sub-transformation unit as A input data. A second nonlinear transformation of the B input data is performed using a second key parameter, the transformed result is output, an XOR operation of the transformed result and the B intermediate data is performed to output an XORed result as B intermediate data, and the B intermediate data is input to a next sub-transformation unit as B input data.
    Type: Grant
    Filed: May 22, 2002
    Date of Patent: August 22, 2006
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Mitsuru Matsui, Toshio Tokita
  • Publication number: 20060050872
    Abstract: It is desired to share one circuit by an encryption unit 200 and a decryption unit 500. A normal data transformation unit (FL) 251 and an inverse data transformation unit (FL?1) 273 are located at point symmetry on a non-linear data transformation unit 220, and a normal data transformation unit (FL) 253 and an inverse data transformation unit (FL?1) 271 are located at point symmetry on the non-linear data transformation unit 220. Therefore, the encryption unit 200 and the decryption unit 500 can be configured using the same circuits.
    Type: Application
    Filed: October 28, 2005
    Publication date: March 9, 2006
    Inventors: Mitsuru Matsui, Toshio Tokita, Junko Nakajima, Masayuki Kanda, Shiho Moriai, Kazumaro Aoki
  • Publication number: 20060050874
    Abstract: It is desired to share one circuit by an encryption unit 200 and a decryption unit 500. A normal data transformation unit (FL) 251 and an inverse data transformation unit ((FL?1)) 273 are located at point symmetry on a non-linear data transformation unit 220, and a normal data transformation unit (FL) 253 and an inverse data transformation unit ((FL?1)) 271 are located at point symmetry on the non-linear data transformation unit 220. Therefore, the encryption unit 200 and the decryption unit 500 can be configured using the same circuits.
    Type: Application
    Filed: October 28, 2005
    Publication date: March 9, 2006
    Inventors: Mitsuru Matsui, Toshio Tokita, Junko Nakajima, Masayuki Kanda, Shiho Moriai, Kazumaro Aoki
  • Publication number: 20060050873
    Abstract: It is desired to share one circuit by an encryption unit 200 and a decryption unit 500. A normal data transformation unit (FL) 251 and an inverse data transformation unit (FL?1) 273 are located at point symmetry on a non-linear data transformation unit 220, and a normal data transformation unit (FL) 253 and an inverse data transformation unit (FL?1) 271 are located at point symmetry on the non-linear data transformation unit 220. Therefore, the encryption unit 200 and the decryption unit 500 can be configured using the same circuits.
    Type: Application
    Filed: October 28, 2005
    Publication date: March 9, 2006
    Inventors: Mitsuru Matsui, Toshio Tokita, Junko Nakajima, Masayuki Kanda, Shiho Moriai, Kazumaro Aoki
  • Publication number: 20060045265
    Abstract: It is desired to share one circuit by an encryption unit 200 and a decryption unit 500. A normal data transformation unit (FL) 251 and an inverse data transformation unit (FL?1) 273 are located at point symmetry on a non-linear data transformation unit 220, and a normal data transformation unit (FL) 253 and an inverse data transformation unit (FL?1) 271 are located at point symmetry on the non-linear data transformation unit 220. Therefore, the encryption unit 200 and the decryption unit 500 can be configured using the same circuits.
    Type: Application
    Filed: October 28, 2005
    Publication date: March 2, 2006
    Inventors: Mitsuru Matsui, Toshio Tokita, Junko Nakajima, Masayuki Kanda, Shiho Moriai, Kazumaro Aoki
  • Publication number: 20020181709
    Abstract: To encrypt another piece of data during encrypting process of a certain piece of data, a memory 55 is provided in parallel with a feedback line 65 which feeds back data from an encrypting module 51using an encryption key K to a selector 54. When an interrupt IT for processing plaintext block data Ni is generated while plaintext block data Mi is processed, ciphertext block data Ci at timing of generation of the interrupt IT is made to be stored in a register 56. The ciphertext block data Ci stored in the memory 55 is made to be selected by the selector 54 at timing of completion of processing the plaintext block data Ni, and processing the plaintext block data Mi+1 is started.
    Type: Application
    Filed: December 6, 2001
    Publication date: December 5, 2002
    Inventors: Toru Sorimachi, Toshio Tokita
  • Publication number: 20020159599
    Abstract: It is desired to share one circuit by an encryption unit 200 and a decryption unit 500. A normal data transformation unit (FL) 251 and an inverse data transformation unit (FL−1) 273 are located at point symmetry on a non-linear data transformation unit 220, and a normal data transformation unit (FL) 253 and an inverse data transformation unit (FL−1) 271 are located at point symmetry on the non-linear data transformation unit 220. Therefore, the encryption unit 200 and the decryption unit 500 can be configured using the same circuits.
    Type: Application
    Filed: January 8, 2002
    Publication date: October 31, 2002
    Inventors: Mitsuru Matsui, Toshio Tokita, Junko Nakajima, Masayuki Kanda, Shiho Moriai, Kazumaro Aoki
  • Patent number: 6466669
    Abstract: The present invention can be applied to a cipher processing apparatus, which includes a function F having a configuration of repeating process and inside of the function F, a function f having a configuration of repeating process is included. According to the invention, the cipher processing apparatus is configured by registers 301 through 303 for temporarily holding data, selectors A through C, 311 through 313, and a function f operating circuit 323 for transforming data. An output data from the function f operating circuit 323 is held in the register C 303, and the selector C 313 selects either to repeat the data transformation by the function operating circuit 323 or not. When a cipher processing apparatus includes a function F having a configuration of repeating process and inside of the function F, a function f having a configuration of repeating process is included, the cipher processing apparatus can be embodied efficiently, which enables to reduce the circuit scale and to save electric power.
    Type: Grant
    Filed: December 31, 1998
    Date of Patent: October 15, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Mitsuru Matsui, Toshio Tokita
  • Publication number: 20020131589
    Abstract: In a data transformation apparatus for transforming two arbitrary pieces of data of A input data and B input data, a first nonlinear transformation of the A input data is performed using a first key parameter, a transformed result is output, an XOR operation of the transformed result and the B input data is performed to output an XORed result as B intermediate data, and the B intermediate data is input to a next sub-transformation unit as B input data. On the other hand, the B input data is input to a next sub-transformation unit as A input data. A second nonlinear transformation of the B input data is performed using a second key parameter, the transformed result is output, an XOR operation of the transformed result and the B intermediate data is performed to output an XORed result as B intermediate data, and the B intermediate data is input to a next sub-transformation unit as B input data.
    Type: Application
    Filed: May 22, 2002
    Publication date: September 19, 2002
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Mitsuru Matsui, Toshio Tokita
  • Patent number: 6415030
    Abstract: In a data transformation apparatus for transforming two arbitrary pieces of data of A input data and B input data, a first nonlinear transformation of the A input data is performed using a first key parameter, a transformed result is output, an XOR operation of the transformed result and the B input data is performed to output an XORed result as B intermediate data, and the B intermediate data is input to a next sub-transformation unit as B input data. On the other hand, the B input data is input to a next sub-transformation unit as A input data. A second nonlinear transformation of the B input data is performed using a second key parameter, the transformed result is output, an XOR operation of the transformed result and the B intermediate data is performed to output an XORed result as B intermediate data, and the B intermediate data is input to a next sub-transformation unit as B input data.
    Type: Grant
    Filed: December 13, 2000
    Date of Patent: July 2, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Mitsuru Matsui, Toshio Tokita
  • Publication number: 20010000708
    Abstract: In a data transformation apparatus for transforming two arbitrary pieces of data of A input data (101) and B input data (102), a first nonlinear transformation of the A input data is performed using a first key parameter (111), a transformed result (109) is output, an XOR operation of the transformed result and the B input data (102) is performed to output an XORed result as B intermediate data (106), and the B intermediate data is input to a next sub-transformation unit (122) as B input data. On the other hand, the B input data (102) is input to a next sub-transformation unit as A input data. A second nonlinear transformation of the B input data (102) is performed using a second key parameter (112), the transformed result is output, an XOR operation of the transformed result and the B intermediate data (106) is performed to output an XORed result as B intermediate data (108), and the B intermediate data is input to a next sub-transformation unit (123) as B input data.
    Type: Application
    Filed: December 13, 2000
    Publication date: May 3, 2001
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Mitsuru Matsui, Toshio Tokita
  • Patent number: 6201869
    Abstract: Data transformation apparatuses and methods for transforming two arbitrary pieces of data of A input data and B input data, wherein a first nonlinear transformation of the A input data is performed using a first key parameter, a transformed result is output, an XOR operation of the transformed result and the B input data is performed to output an XORed result as B intermediate data, and the B intermediate data is input to a next sub-transformation unit as B input data. On the other hand, the B input data is input to a next sub-transformation unit as A input data. A second nonlinear transformation of the B input data is performed using a second key parameter, the transformed result is output, an XOR operation of the transformed result and the B intermediate data is performed to output an XORed result as B intermediate data, and the B intermediate data is input to a next sub-transformation unit as B input data.
    Type: Grant
    Filed: April 28, 1997
    Date of Patent: March 13, 2001
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Mitsuru Matsui, Toshio Tokita
  • Patent number: 5912905
    Abstract: The present invention provides an error-correcting encoder and an error-correcting decoder which encode/decode a plurality of information symbols in parallel with a reduced number of shifts, which enables a reduction in the processing time. The error-correcting encoder of the invention includes a shift register including stages equal to a predetermined number of check symbols for inputting different information symbols in parallel from a plurality of input terminals. The encoder also includes a Galois field multiplier for multiplying each coefficient and a Galois field adder to obtain the predetermined number of check symbols from the information symbols. The encoder can generate the predetermined number of check symbols with shifts, the number of which is reduced according to the number of parallel inputs.
    Type: Grant
    Filed: February 20, 1997
    Date of Patent: June 15, 1999
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yasuyuki Sakai, Hideo Yoshida, Toshio Tokita
  • Patent number: 5699368
    Abstract: The present invention provides an error-correcting encoder and an error-correcting decoder which encode/decode a plurality of information symbols in parallel with a reduced number of shifts, which enables a reduction in the processing time. The error-correcting encoder of the invention includes a shift-register including stages equal to a predetermined number of check symbols for inputting different information symbols in parallel from a plurality of input terminals. The encoder also includes a Galois field multiplier for multiplying each coefficient and a Galois field adder to obtain the predetermined number of check symbols from the information symbols. The encoder can generate the predetermined number of check symbols with shifts, the number of which is reduced according to the number of parallel inputs.
    Type: Grant
    Filed: February 7, 1995
    Date of Patent: December 16, 1997
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yasuyuki Sakai, Hideo Yoshida, Toshio Tokita