COMMUNICATION SYSTEM, COMMUNICATION DEVICE, KEY MANAGEMENT APPARATUS, AND COMMUNICATION METHOD

• US 20160014100A1
• Filed: 07/06/2015
• Published: 01/14/2016
• Est. Priority Date: 07/10/2014
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Inventors: MATSUO, Masakatsu
• Granted Patent: US 9,654,455 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04L 2463/062 applying encryption of the keys cryptographic mechanisms or cryptographic arrangements for key distribution using key encryption key H04L9/0822
• CPC Class Codes: H04L 63/0435 wherein the sending and receiving network entities apply symmetric encryption, i.e. same key used for encryption and decryption cryptographic mechanisms or cryptographic arrangements for symmetric key encryption H04L9/06
• CPC Class Codes: H04L 63/062 for key distribution, e.g. centrally by trusted party cryptographic mechanisms or cryptographic arrangements for key distribution involving a central third party H04L9/0819
• CPC Class Codes: H04L 63/08 for authentication of entities cryptographic mechanisms or cryptographic arrangements for entity authentication H04L9/32

Abstract

A communication system includes a first communication device, a second communication device, and a key management apparatus. The second communication device generates a random number, generates encrypted data using an encryption key, encrypts the random number, generates key information data, and transmits the key information data, identification information of the second communication device, and the encrypted data to the first communication device. The first communication device receives the key information data, the identification information, and the encrypted data, transmits the key information data and the identification information to the key management apparatus, receives the encryption key from the key management device, decodes the encrypted data and obtains the predetermined data using the received encryption key. The key management apparatus receives the key information data and the identification information, decodes the key information data, acquires the random number, and transmits the encryption key to the first communication device.

Claims

1. A communication system comprising:

a first communication device;

a second communication device; and

a key management apparatus,

wherein the second communication device includes

a random number generation unit that generates a random number

a first encrypting processing unit that, using an encryption key that is based on the random number, encrypts predetermined data and thus generates encrypted data, and that, using a key of the second communication device, encrypts the random number and thus generates key information data, and

a first communication unit that transmits the key information data, identification information of the second communication device, and the encrypted data to the first communication device,

wherein the first communication device includes

a second communication unit that receives the key information data, the identification information of the second communication device, and the encrypted data from the second communication device, transmits the key information data and the identification information of the second communication device, which are received, to the key management apparatus, and receives the encrypted key from the key management apparatus, and

a second decoding processing unit that, using the received encryption key, decodes the encrypted data and obtains the predetermined data,

wherein the key management apparatus includes

a third communication unit that receives the key information data and the identification information of the second communication device from the first communication device, and

a first decoding processing unit that decodes the key information data and thus acquires the random number, using a key of the second communication device, which corresponds to the identification information of the second communication device, and

wherein the third communication unit transmits the encrypted key that is based on the acquired random number, to the first communication device.

2. The communication system of claim 1,

wherein the second communication device includes a first key generation unit that generates the encryption key from the random number using a unidirectional function, and

wherein the key management apparatus includes a second key generation unit that generates the encryption key from the random number using the unidirectional function.

3. The communication system of claim 1,

wherein the key management device includes a second encrypting processing unit that encrypts the encryption key with a key of the first communication device,

wherein the third communication unit transmits the encrypted encryption key to the first communication device,

wherein the second communication unit receives the encrypted encryption key from the key management apparatus, and

wherein the second decoding processing unit decodes the received encryption key with the key of the first communication device and decodes the encrypted data using the decoded encryption key.

4. The communication system of claim 1,

wherein the first communication unit and the second communication unit mutually perform short-distance wireless communication.

5. The communication system of claim 1,

wherein the second communication unit transmits identification information of the first communication device to the key management apparatus, and

wherein the key management apparatus includes an authentication unit that authenticates the first communication device using the identification information of the first communication device.

6. The communication system of claim 1,

wherein the first communication device and the second communication device are communication terminals, and

wherein the second communication device includes a data acquisition unit that acquires the predetermined data from a data providing server.

7. A communication device that provides predetermined data to a different communication device, the communication device comprising:

a random number generation unit that generates a random number;

an encrypting processing unit that encrypts predetermined data and thus generates encryption data, using an encryption key that is based on the random number, and encrypts the random number and thus generates key information data using a key of the communication device, and

a communication unit that transmits the key information data, identification information of the communication device, and the encrypted data to the different communication device.

8. A communication device to which predetermined data from a different communication device is provided, the communication device comprising:

a communication unit that receives

key information data that results from encrypting a random number using a key of the different communication device, identification information of the different communication device, and encrypted data that results from encrypting the predetermined data using an encryption key that is based on the random number, from the different communication device, transmits the received key information data and the identification information of the different communication device to the key management apparatus, and receives the encryption key from the key management apparatus; and

a decoding processing unit that, using the received encryption key, decodes the encrypted data and obtains the predetermined data.

9. A key management apparatus that is connected to a first communication device to which a second communication device provides predetermined data, through a network, the key management apparatus comprising:

a communication unit that receives key information data that results from encrypting a random number using a key of the second communication device, and identification information of the second communication device, from the first communication device; and

a decoding processing unit that decodes the key information data and thus acquires the random number, using a key of the second communication device, which corresponds to the identification information of the second communication device,

wherein the communication unit transmits an encryption key that is based on the acquired random number, to the first communication device.

10. A communication method for use in a communication system that includes a first communication device, a second communication device, and a key management apparatus, the method comprising:

generating a random number in the second communication device;

encrypting predetermined data and thus generating encrypted data using an encryption key that is based on the random number in the second communication device;

encrypting the random number and thus generating key information data using a key of the second communication device in the second communication device;

transmitting the key information data, identification information of the second communication device, and the encrypted data to the first communication device in the second communication device;

receiving the key information data, the identification information of the second communication device, and the encrypted data from the second communication device in the first communication device;

transmitting the key information data and the identification information of the second communication device to the key management apparatus in the first communication device;

receiving the key information data and the identification information of the second communication device from the first communication device in the key management apparatus;

decoding the key information data and thus acquiring the random number using a key of the second communication device, which corresponds to the identification information of the second communication device in the key management apparatus;

transmitting an encryption key that is based on the acquired random number, to the first communication device in the key management apparatus;

receiving the encryption key from the key management apparatus in the first communication device; and

decoding the encrypted data and obtaining the predetermined data using the received encryption key in the first communication device.