Network interface device

1. A network interface card (NIC) comprising:

a first area of trust comprising a first part of the NIC, wherein a first kernel is in the first area of trust and the first area of trust is associated with a first address space;

a second area of trust comprising a second part of the NIC different to the first part, wherein a second kernel is in the second area of trust and the second area of trust is associated with a second address space, separate from the first address space; and

a communication link between the first area of trust and the second area of trust,

wherein the first area of trust is provided with isolation circuitry associated with the first kernel and configured to control which data is passed to the second area of trust via the communication link.

2. The network interface device as claimed in claim 1 , wherein hardware provided in one area of trust has restricted access to hardware in the other area of trust, wherein the first and second area of trusts comprise non-overlapping hardware and the first and second kernels are different.

3. The network interface device as claimed in claim 1 , wherein the isolation circuitry is configured to use header values of the data to determine which data can be passed to the other of the first and second areas of trust.

4. The network interface device as claimed in claim 1 , wherein the isolation circuitry associated with the first area of trust is configured to modify received data to be in a form used in the first area of trust.

5. The network interface device as claimed in claim 1 , wherein the isolation circuitry associated with the first area of trust is configured to modify data to be output from the first area of trust to remove a part of the data required in the first area of trust but is not required in the second area of trust.

6. The network interface device as claimed in claim 1 , wherein the isolation circuitry is configured to determine adherence to a communication link protocol of the communication link.

7. The network interface device as claimed in claim 1 , wherein the isolation circuitry is configured to terminate one or more request indicating one or more of reset or reconfiguration of one or more of the first and second kernels.

8. The network interface device as claimed in claim 1 , wherein one or more other kernels sharing a same privilege with the first kernel are in the first area of trust and are associated with the first kernel, and wherein the first kernel comprises at least one of an entry point module or an exist point module of the first area of trust and is associated with the isolation circuitry.

9. The network interface device as claimed in claim 1 , wherein the first area of trust is associated with a first data flow and the second area of trust is associated with a second different data flow.

10. The network interface device as claimed in claim 1 , wherein the first area of trust is associated with a first application and the second area of trust is associated with a second, different, application.

11. The network interface device as claimed in claim 1 , wherein the first kernel is configured to be one of inserted and removed at run time.

12. The network interface device as claimed in claim 11 , wherein the network interface device is configured such that once the first kernel is loaded, a hardware linker for the first kernel is provided linking the first kernel to another kernel, the hardware linker being configured such that only data associated with an allowed data flow can be one or more of received and output by the first kernel.

13. The network interface device as claimed in claim 12 , wherein the hardware linker provides the communication link between the first and second areas of trust and at least a part of the isolation circuitry in the first area of trust.

14. The network interface device as claimed in claim 1 , wherein the first kernel of the first area of trust is configured to process data and to provide a part of the data to the second kernel of the second area of trust.

15. The network interface device as claimed in claim 1 , wherein the first kernel of the first area of trust is configured to at least one of: at least partially protocol process data; decrypt data; or encrypt data.

16. The network interface device as claimed in claim 1 , wherein the second kernel of the second area of trust is configured to support a data storage application.

17. The network interface device as claimed in claim 1 , wherein the first area of trust is configured to provide data to a third area of trust in the network interface device.

18. The network interface device as claimed in claim 17 , wherein the isolation circuitry is configured to prevent data from one of the second or third areas of trust from being pushed to the other of the second or third areas of trust.

19. The network interface device as claimed in claim 1 , wherein at least one of the first and second area of trust extends to a host computing device.

20. A method in a network interface device comprising:

linking a first area of trust and a second area of trust, the first area of trust comprising a first part of the network interface card (NIC), wherein a first kernel is in the first area of trust and the first area of trust is associated with a first address space, and the second area of trust comprising a second part of the network interface card (NIC) different to the first part, wherein a second kernel is in the second area of trust and the second area of trust is associated with a second address space, separate from the first address space; and

using isolation circuitry associated with the first kernel to control data which is passed between the first area of trust and the second area of trust.