Server, method of group key notification and program

Patent metadata

Field	Value
Publication number	US-9258284-B2
Application number	US-201414168353-A
Country	US
Kind code	B2
Filing date	Jan 30, 2014
Priority date	Jan 31, 2013
Publication date	Feb 9, 2016
Grant date	Feb 9, 2016

Abstract

According to one embodiment, a server includes a message communicator, a key information storage, and a key controller. The message communicator is configured to communicate a message to a client. The key information storage is configured to store key information including at least a key value being value of key, a validity term of key, and assignment information of key. The key controller is configured to generate a key notification message including a key value of the client and a key update time when the message communicator receives a key request message from an authenticated client. The key value is corresponding with the assignment of the key information. The key update time decides from the validity term of the key and a validity term of authentication succeeded state of the client. The message communicator transmits the key notification message to the client.

First claim

What is claimed is:

1. A server comprising:
a message communicator configured to communicate a message to a client;
a key information storage configured to store information about a key, the information including at least a key value, a first validity term, and assignment information;
a key controller configured to generate a notification message about the key, the notification message including a value of a client key and an update time when the message communicator receives a key request message from an authenticated client, the key value corresponding with the assignment information, the update time deciding from the first validity term and a second validity term of authentication succeeded state of the client;
wherein the message communicator transmits the notification message to the client;
a client information storage configured to store client information having a need to authenticate the client; and
an authenticator configured to authenticate the client from an authentication request message and the client information when the message communicator receives the authentication request message,
wherein the key controller generates the notification message including the key value and the key update time when the message communicator receives the key request message from the authenticated client, the key value corresponding with the assignment information, the update time deciding from the first validity time and the second validity time, wherein the client information includes address information of the client, and
wherein the key controller judges whether to include the update time in the notification message from the address information.

2. The server according to claim 1 , wherein the key controller decides on the update time to be an equal or earlier time than the second validity term when the second validity term is equal or earlier than the first validity term.

3. The server according to claim 1 , wherein the key controller decides on the update time to be an equal or earlier time than the first validity term when the first validity term is equal or earlier than the second validity term.

4. The server according to claim 2 , wherein the key controller decides on the update time to be operation timing when the operation timing of the client is equal or earlier time than the second validity term.

5. The server according to claim 3 , wherein the key controller decides on the update time to be operation timing when the operation timing of the client is equal or earlier time than the first validity term.

6. A method of group key notification comprising;
confirming whether a client received an authentication message or not;
generating a notification message about a key, the notification message including a value of a key of the client and an update time when the authentication message was received from the client, the value corresponding with information about the key, the information including at least a key value, a first validity term, and assignment information, the update time deciding from the first validity term and a second validity term of authentication succeeded state of the client;
transmitting the notification message to the client;
authenticating the client from the authentication message and client information when the authentication message is received from an authenticated client;
generating the notification message including the value and the update time when the authentication message is received from the authenticated client, the key value corresponding with the assignment information, the update time deciding from the first validity time and the second validity time, wherein the client information includes address information of the client, and
judging whether to include the update time in the notification message from the address information.

7. A computer program product comprising a non transitory computer-readable medium containing a program executed by a computer, the program causing the computer to execute:
confirming whether the client received an authentication message or not;
generating a notification message about a key, the notification message including a value of a key of the client and an update time when the authentication message was received from the client, the value corresponding with information about the key, the information including at least a key value, a first validity term, and assignment information, the update time deciding from the first validity term and a second validity term of authentication succeeded state of the client;
transmitting the notification message to the client;
authenticating the client from the authentication message and client information when the authentication message is received from an authenticated client;
generating the notification message including the value and the update time when the authentication message is received from the authenticated client, the key value corresponding with the assignment information, the update time deciding from the first validity time and the second validity time, wherein the client information includes address information of the client, and
judging whether to include the update time in the notification message from the address information.

Assignees

• Toshiba Kk

Inventors

• Tanaka Yasuyuki

Classifications

• H04L63/104

  Grouping of entities · CPC title

• H04L63/065

  for group communications (cryptographic mechanisms or cryptographic arrangements for key management involving conference or group key H04L9/0833) · CPC title

• H04L63/0846

  using time-dependent-passwords, e.g. periodically changing passwords · CPC title

• H04L63/061 Primary

  for key exchange, e.g. in peer-to-peer networks (cryptographic mechanisms or cryptographic arrangements for key agreement H04L9/0838) · CPC title