COMMUNICATIONS APPARATUS, COMMUNICATIONS SYSTEM, AND METHOD OF SETTING CERTIFICATE

• US 20100077207A1
• Filed: 12/03/2009
• Published: 03/25/2010
• Est. Priority Date: 09/12/2003
• Status: Active Grant

• Current Assignee: Tatsuya Imai
• Original Assignee: Tatsuya Imai
• Inventors: IMAI, Tatsuya
• Granted Patent: US 8,291,225 B2
• Time in Patent Office: Days
• US Class Current: 713/156
• CPC Class Codes: G06F 21/33 using certificates
• CPC Class Codes: H04L 63/0823 using certificates cryptographic mechanisms or cryptographic arrangements for entity authentication involving certificates H04L9/3263
• CPC Class Codes: H04L 63/166 at the transport layer

Abstract

An apparatus in a system which includes at least a high-level apparatus and a plurality of low-level apparatuses, said apparatus being one of the low-level apparatuses. The apparatus includes a storage unit configured to store an individual certificate set and a common certificate set and a communication unit configured to transmit own authentication information to the high level apparatus to allow the high level apparatus to perform decryption to authenticate the validity of the apparatus.

Claims

1. An apparatus in a system which includes at least a high-level apparatus and a plurality of low-level apparatuses, said apparatus being one of the low-level apparatuses, the apparatus comprising:

a storage unit configured to store an individual certificate set and a common certificate set,

wherein the common certificate set is the same common certificate set stored in advance on the other of the plurality of low-level apparatuses, said common certificate set being used for storing a new individual certificate set in the apparatus, and

wherein the individual certificate set is configured to include own authentication information and an individual root-key certificate, the own authentication information including information uniquely identifying the apparatus, the individual root key certificate being the same for the other of the plurality of low-level apparatuses and is used to authenticate the validity of the high level apparatus; and

a communication unit configured to transmit the own authentication information to the high level apparatus to allow the high level apparatus to perform decryption to authenticate the validity of the apparatus.

2. The apparatus according to claim 1, wherein the common certificate set does not include information uniquely identifying the apparatus and is configured to include a common public-key certificate, a common private-key certificate, and a common root-key certificate, the common root-key certificate being used by the high-level apparatus to determine a type of the plurality of low-level apparatuses.

3. The apparatus according to claim 1, wherein the own authentication information is configured to include an individual public-key certificate and an individual private key certificate, the individual public-key certificate including information uniquely identifying the apparatus, the individual private-key certificate being a private key corresponding to the individual public-key certificate and used by the apparatus to perform encryption, and the individual root key certificate is the same as an individual root-key certificate of the high-level apparatus.

4. A system which includes at least a high-level apparatus and a plurality of low-level apparatuses, at least one of the low-level apparatuses comprising:

a storage unit configured to store an individual certificate set and a common certificate set,

wherein the common certificate set is the same common certificate set stored in advance on the other of the plurality of low-level apparatuses, said common certificate set being used for storing a new individual certificate set in the low-level apparatus, and

wherein the individual certificate set is configured to include own authentication information and an individual root-key certificate, the own authentication information including information uniquely identifying the apparatus, the individual root key certificate being the same for the other of the plurality of low-level apparatuses and is used to authenticate the validity of the high level apparatus; and

a communication unit configured to transmit the own authentication information to the high level apparatus to allow the high level apparatus to perform decryption to authenticate the validity of the low-level apparatus.

5. The system according to claim 4, wherein the common certificate set does not include information uniquely identifying the low-level apparatus and is configured to include a common public-key certificate, a common private-key certificate, and a common root-key certificate, the common root-key certificate being used by the high-level apparatus to determine a type of the plurality of low-level apparatuses.

6. The system according to claim 4, wherein the own authentication information is configured to include an individual public-key certificate and an individual private key certificate, the individual public-key certificate including information uniquely identifying the apparatus, the individual private-key certificate being a private key corresponding to the individual public-key certificate and used by the apparatus to perform encryption, and the individual root key certificate is the same as an individual root-key certificate of the high-level apparatus.

7. A method of communicating implemented on an apparatus in a system which includes at least a high-level apparatus and a plurality of low-level apparatuses, said apparatus being one of the low-level apparatuses, the method comprising:

storing, at the apparatus, an individual certificate set and a common certificate set,

wherein the common certificate set is the same common certificate set stored in advance on the other of the plurality of low-level apparatuses, said common certificate set being used for storing a new individual certificate set in the apparatus, and

wherein the individual certificate set is configured to include own authentication information and an individual root-key certificate, the own authentication information including information uniquely identifying the apparatus, the individual root key certificate being the same for the other of the plurality of low-level apparatuses and is used to authenticate the validity of the high level apparatus; and

transmitting, at the apparatus, the own authentication information to the high level apparatus to allow the high level apparatus to perform decryption to authenticate the validity of the apparatus.

8. The method according to claim 7, wherein the common certificate set does not include information uniquely identifying the apparatus and is configured to include a common public-key certificate, a common private-key certificate, and a common root-key certificate, the common root-key certificate being used by the high-level apparatus to determine a type of the plurality of low-level apparatuses.

9. The method according to claim 7, wherein the own authentication information is configured to include an individual public-key certificate and an individual private key certificate, the individual public-key certificate including information uniquely identifying the apparatus, the individual private-key certificate being a private key corresponding to the individual public-key certificate and used by the apparatus to perform encryption, and the individual root key certificate is the same as an individual root-key certificate of the high-level apparatus.