Patent ID: 9258284
Filing Date: 2016-02-09
CPC Classification: H04L

Claim Text:
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.