Encryption communications using digital certificates with increased security

• US 20070234047A1
• Filed: 03/21/2007
• Published: 10/04/2007
• Est. Priority Date: 03/30/2006
• Status: Abandoned Application

• Current Assignee: Brother Kogyo Kabushiki Kaisha (Brother Industries Limited)
• Original Assignee: Brother Kogyo Kabushiki Kaisha (Brother Industries Limited)
• Inventors: Miyazawa, Masafumi
• Application Number:
  US11/723,583
• Publication Number:
  US 20070234047A1
• Time in Patent Office: Days
• US Class Current: 713/158
• CPC Class Codes: H04L 9/3268 using certificate validation, registration, distribution or revocation, e.g. certificate revocation list [CRL]
• CPC Class Codes: H04L 9/3271 using challenge-response

Abstract

An apparatus for use in implementing encrypted communications using a digital certificate is disclosed. The apparatus is configured to include a memory storing therein the digital certificate; and a selective-transmit controller, upon receipt of a request from a requester for the encrypted communications using the digital certificate, determining whether or not the digital certificate is valid, transmitting the digital certificate to the requestor if the digital certificate is valid, and not transmitting the digital certificate to the requester if the digital certificate is not valid.

Claims

1. An apparatus for use in implementing encrypted communications using a digital certificate, comprising:

a memory storing therein the digital certificate; and

a selective-transmit controller, upon receipt of a request from a requester for the encrypted communications using the digital certificate, determining whether or not the digital certificate is valid, transmitting the digital certificate to the requestor if the digital certificate is valid, and not transmitting the digital certificate to the requestor if the digital certificate is not valid.

2. The apparatus according to claim 1, wherein the selective-transmit controller includes:

a receiver receiving from the requestor the request for the encrypted communications;

a determining unit determining whether or not the digital certificate is valid; and

a transmitter transmitting the digital certificate to the requestor if the determining unit determined that the digital certificate was valid, and not transmitting the digital certificate to the requestor if the determining unit determined that the digital certificate was not valid.

3. The apparatus according to claim 1, wherein the selective-transmit controller is configured, if the digital certificate was determined not to be valid, not to transmit the digital certificate to the requester, and to inhibit encrypted communications between the requester and a destination from being implemented.

4. The apparatus according to claim 1, wherein the memory has stored therein a plurality of digital certificates in association with the requestor, and

the selective-transmit controller is configured, if determined that at least one of the plurality of digital certificates was valid, to transmit at least one of the at least one valid digital certificate to the requestor.

5. The apparatus according to claim 4, wherein the selective-transmit controller is configured, if determined that at least one of the plurality of digital certificates was valid, to transmit at least one of the at least one valid digital certificate to the requester, and to permit encrypted communications between the requestor and a destination.

6. The apparatus according to claim 1, configured to be communicable with a responder managing a certificate revocation list, wherein the selective-transmit controller determines, through communications with the responder, whether or not the digital certificate is on the certificate revocation list, and determines that the digital certificate is not valid, if the digital certificate is on the certificate revocation list.

7. The apparatus according to claim 6, wherein the memory has stored therein a plurality of digital certificates in association with the requestor, and

the selective-transmit controller is configured to transmit to the responder at a time all sets of information required to determine the validity of every one of the plurality of digital certificates by reference to the certificate revocation list.

8. A method of for use in implementing encrypted communications using a digital certificate, comprising:

a reception step of receiving a request from a requester for the encrypted communications using the digital certificate;

a determination step of determining, upon receipt of the request, whether or not the digital certificate is valid; and

a selective-transmit step of transmitting the digital certificate to the requester if the digital certificate is valid, and not transmitting the digital certificate to the requester if the digital certificate is not valid.

9. The method according to claim 8, wherein the selective-transmit step includes:

a permit sub-step of permitting a transmission of the digital certificate to the requester, if the digital certificate was determined to be valid; and

an inhibit sub-step of inhibiting a transmission of the digital certificate to the requester, if the digital certificate was determined not to be valid.

10. A computer-readable medium having stored therein a program which, when executed by a computer, implements encrypted communications using a digital certificate, the program comprising:

instructions for receiving a request from a requester for the encrypted communications using the digital certificate;

instructions for determining, upon receipt of the request, whether or not the digital certificate is valid; and

instructions for transmitting the digital certificate to the requestor if the digital certificate is valid, and not transmitting the digital certificate to the requestor if the digital certificate is not valid.