Securely transmitting data in a data stream

1. A computer-implemented method of receiving data by a backend device from an Internet of Things device, the method comprising:

receiving, by the backend device, an encrypted data stream from the Internet of Things device using a first connection, the encrypted data stream including unencrypted sensor data;

decrypting, by the backend device, the encrypted data stream received from the Internet of Things device, to obtain a decrypted data stream;

receiving, by the backend device, metadata from the Internet of Things device using a second connection, the metadata identifying a location of the unencrypted sensor data in the decrypted data stream;

identifying, by the backend device, the unencrypted sensor data in the decrypted data stream based on the location provided by the metadata from the Internet of Things device, said location being part of the decrypted data stream; and

encrypting, by the backend device, the unencrypted sensor data identified in the decrypted data stream.

2. The computer-implemented method of claim 1 , wherein the encrypted data stream transmitted using the first connection has been encrypted by the Internet of Things device using a first cipher, and the metadata transmitted using the second connection has been encrypted by the Internet of Things device using a second cipher different from the first cipher.

3. The computer-implemented method of claim 1 , wherein the metadata comprises a cryptographic key, and the method comprises causing the backend device to encrypt the unencrypted sensor data in a second data stream using the cryptographic key.

4. A system for transmitting data from an Internet of Things device to a backend device, the system comprising:

the Internet of Things device, comprising a processor implemented with one or more physical circuit components, the Internet of Things device being configured to:

receive a data stream and a location of unencrypted sensor data in the data stream;

encrypt the data stream, to obtain an encrypted data stream; and

transmit the encrypted data stream to the backend device using a first connection;

transmit metadata using a second connection, the metadata identifying the location of the unencrypted sensor data in the data stream;

the backend device, comprising a second processor implemented with one or more further physical circuit components, the backend device being configured to:

receive the encrypted data stream from the Internet of Things device using the first connection;

receive the metadata indicating the location of the unencrypted sensor data in the data stream using the second connection;

decrypt the encrypted data stream, to obtain a decrypted data stream;

identify the unencrypted sensor data in the decrypted data stream based on the location; and

encrypt the unencrypted sensor data identified in the decrypted data stream.

5. The system according to claim 4 , wherein the Internet of Things device is configured to encrypt the data stream using a first cipher, and configured to encrypt the metadata using a second cipher different from the first cipher.

6. The system according to claim 4 , wherein the metadata comprises a cryptographic key, the backend device further being configured to encrypt the unencrypted sensor data using the cryptographic key.

7. A non-transitory computer-readable storage medium comprising instructions which, when executed by a processor of a backend device, cause the processor to carry out the steps of:

obtaining an encrypted data stream received from an Internet of Things device using a first connection, the encrypted data stream including unencrypted sensor data;

decrypting the encrypted data stream received by the backend device from the Internet of Things device, to obtain a decrypted data stream;

obtaining metadata received from the Internet of Things device using a second connection, the metadata identifying a location of the unencrypted sensor data in the decrypted data stream;

identifying the unencrypted sensor data in the decrypted data stream based on the location provided by the metadata from the Internet of Things device, said location being part of the decrypted data stream; and

encrypting the unencrypted sensor data identified in the decrypted data stream.