Authentication device and method using electronic certificate files having hierarchical relationship

• US 20090019519A1
• Filed: 01/18/2008
• Published: 01/15/2009
• Est. Priority Date: 01/19/2007
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: KIKUCHI, Yusaku
• Granted Patent: US 8,473,737 B2
• Time in Patent Office: Days
• US Class Current: 726/2
• CPC Class Codes: H04L 9/3247 involving digital signatures
• CPC Class Codes: H04L 9/3263 involving certificates, e.g. public key certificate [PKC] or attribute certificate [AC]; Public key infrastructure [PKI] arrangements network architectures or network communication protocols for supporting authentication of entities using certificates in a packet data network H04L63/0823

Abstract

This authentication device includes: a volatile memory; a non-volatile memory which stores a plurality of electronic certificate files; a unit which refers to the non-volatile memory upon start-up, and which stores a hierarchical relationship between the plurality of electronic certificate files in the volatile memory; a unit for searching for a desired electronic certificate file based upon the hierarchical relationship between the plurality of electronic certificate files in the volatile memory; and an authentication unit which performs authentication using the electronic certificate file which has been found by the search unit.

Claims

1. An authentication device, comprising:

a volatile memory;

a non-volatile memory which stores a plurality of electronic certificate files;

a storage unit which refers to the non-volatile memory upon start-up, and which stores a hierarchical relationship between the plurality of electronic certificate files in the volatile memory;

a search unit which searches for a desired electronic certificate file based upon the hierarchical relationship between the plurality of electronic certificate files in the volatile memory; and

an authentication unit which performs authentication using the electronic certificate file which has been found by the search unit.

2. An authentication device according to claim 1, wherein, if the CA (Certificate Authority) which issued the electronic certificate file is an intermediate CA which has been authenticated by a root CA, the hierarchical relationship between the plurality of electronic certificate files is a hierarchical relationship from the intermediate CA to the root CA.

3. An authentication device according to claim 2, further comprising.

an automatic installation unit which, when predetermined data has been downloaded from a server which is authenticated by the intermediate CA, stores in the non-volatile memory an electronic certificate file issued by the intermediate CA which has been downloaded along with the downloaded data;

and

a structured entity creation unit which appends, to a list structured entity in the volatile memory, an information item which corresponds to the electronic certificate file which has been acquired by the automatic installation unit.

4. An authentication device according to claim 3, wherein identification information is appended to the electronic certificate file which has been installed by the automatic installation unit, for identifying an electronic certificate file which has been explicitly installed by the user.

5. An authentication method performed by an authentication device which comprises a volatile memory and a non-volatile memory which stores a plurality of electronic certificate file,

referring to the non-volatile memory upon start-up of the authentication device, and storing a hierarchical relationship between the plurality of electronic certificate files in the volatile memory;

referring to the hierarchical relationship between the plurality of electronic certificate files in the volatile memory, and searching for a desired electronic certificate file; and

performing authentication using the electronic certificate file which has been found.