Communication device and communication method

Abstract

The present invention realizes the improvement of the security of communication. A server (101) receives encrypted data (121) encrypted with ECU information (120) using key information (111-1#C) and identification information (112-1#C) from an in-vehicle device (102). After acceptance, the server (101) judges based on the identification information (112-1#C) whether the identification information of the key to be used next by the identification information (112-1) is stored. The server (101) judges the identification information of the next key to be used for which no identification information (112-1) is stored, and obtains key information (111-2#S) and identification key information (111 -2) identification information (112-2#S). Server (101) encrypts key information (111-2#S) and identification information (112-2#S) using key information (111-1#S), and sends encrypted data to vehicle-mounted device (102) ( 122), and identification information (112-1#S).

Description

technical field [0001] The present invention relates to a communication program, a recording medium, a communication device, and a communication method. Background technique [0002] Conventionally, there is a technique of communicating between a server and a client using a common key encryption method. For example, there is a client-server system in which the client and the server have a key storage unit for storing a plurality of predetermined common keys of different generations, and use one of the plurality of predetermined common keys Technology for communicating. [0003] In addition, as a related technique, there is, for example, a technique in which a mobile device is used for authentication of rewriting qualification of information on an on-vehicle device in communication between an on-vehicle device and a server in a vehicle. In addition, there is a technique of transferring the communication state from the information communication device to the vehicle-mounted ...

AI Technical Summary

Problems solved by technology

[0011] However, in the prior art, the more the same shared key is used to communicate with the communication destination, the higher the possibility that the shared key will be leaked to a third party

Therefore, when changing the common key, if the next common key is encrypted and transmitted using the common key repeatedly used for communication with the communication destination, the possibility that the next common key will be leaked to a third party increases.

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