Patent ID: 9178881
Filing Date: 2015-11-03
Classification: G06F,H04L

Abstract:
1. A method at a server to ensure the genuineness of a client device, comprising: receiving a request from the client device to access digital content; in response to the request, issuing a genuineness challenge to the client device, the genuineness challenge comprises a payload and a message authentication code of the payload which are generated by the server; pursuant to the issuing, receiving a response from the client device, wherein: to verify that the second data element was derived from the first data element, calculating a comparison value of the second data element by inputting the first data element of the client device and a first secret key of the server to a first key derivation function, and verifying that the comparison value of the second data element matches the second data element of the client device in the response; to calculate the key of the client device using the first and second data elements in the response, to provide a calculated key, inputting the first and second data elements of the client device and a second secret key of the server to a second key derivation function; validating the message authentication code of the message by using the message and the calculated key to provide a comparison message authentication code of the message, and verifying that the comparison message authentication code of the message matches the message authentication code of the message which is generated by the client device; validating the copy of the message authentication code of the payload by using the copy of the payload to provide a comparison message authentication code of the payload, and verifying that the comparison message authentication code of the payload matches the message authentication code of the payload which is generated by the server; and responsive to the verifying that the second data element was derived from the first data element, the validating the message authentication code of the message and the validating the copy of the message authentication code of the payload, fulfilling the request by the client device to access the digital content, wherein the genuineness of the client device is ensured without using asymmetric cryptography.