Cross-domain state synchronization

1. A multi-domain relay apparatus comprising:

a hardware processor configured to establish a first communication channel between an anchor peer in a first security domain and the multi-domain relay apparatus, and a second communication channel between an anchor peer in a second security domain and the multi-domain relay apparatus, wherein the first and second security domains are logically isolated from each other and share a blockchain ledger; and

a network interface configured to receive a gossip message originated from the anchor peer in the first security domain, wherein the gossip message comprises block content from the blockchain ledger,

wherein the hardware processor is further configured to verify, via the multi-domain relay apparatus, that the block content within the gossip message does not violate a cross-domain security policy of the first and second security domains, and in response to verification of the block content, update an endpoint of the gossip message with an address of the anchor peer in the second security domain, and

the hardware processor is further configured to control the network interface to transmit the updated gossip message to the anchor peer in the second security domain.

2. The multi-domain relay apparatus of claim 1 , wherein the hardware processor is further configured to replace an address of the anchor peer in the first security domain with the address of the anchor peer in the second security domain within the gossip message, prior to transmitting the updated gossip message to the anchor peer in the second security domain.

3. The multi-domain relay apparatus of claim 1 , wherein the block content comprises block hashes, block numbers, and transaction data stored on an instance of the blockchain ledger of the domain anchor peer in the first security domain.

4. The multi-domain relay apparatus of claim 1 , wherein the first security domain comprises a high side of a blockchain network and the second security domain comprises a low side of the blockchain network.

5. The multi-domain relay apparatus of claim 1 , wherein cross-domain security policy identifies data which cannot pass from the first security domain to the second security domain.

6. The multi-domain relay apparatus of claim 1 , wherein the cross-domain security policy identifies data which is allowed for storage in the first and second security domains.

7. The multi-domain relay apparatus of claim 1 , wherein the hardware processor is further configured to verify that sensitive channel membership information of the first security domain is not included within the gossip message prior to transmission of the updated gossip message to the second blockchain peer.

8. The multi-domain relay apparatus of claim 1 , wherein the network interface is further configured to receive a request to transmit the gossip message from the domain anchor peer in the second security domain, and the hardware processor is configured to transmit the request to transmit to the domain anchor peer in the first security domain.

9. A method comprising:

establishing a first communication channel between an anchor peer in a first security domain and a multi-domain relay and a second communication channel between an anchor peer in a second security domain and the multi-domain relay, wherein the first and second security domains are logically isolated from each other and share a blockchain ledger;

receiving a gossip message originated from the anchor peer in the first security domain, wherein the gossip message comprises block content from the blockchain ledger;

verifying, via the multi-domain relay, that block content within the gossip message does not violate a cross-domain security policy of the first and second security domains;

in response to verifying the block content, updating an endpoint of the gossip message with an address of the anchor peer in the second security domain; and

transmitting the updated gossip message to the anchor peer in the second security domain.

10. The method of claim 9 , wherein the updating comprises replacing an address of the anchor peer in the first security domain with the address of the anchor peer in the second security domain within the gossip message, prior to transmitting the updated gossip message to the anchor peer in the second security domain.

11. The method of claim 9 , wherein the block content comprises block hashes, block numbers, and transaction data stored on an instance of the blockchain ledger of the anchor peer in the first security domain.

12. The method of claim 9 , wherein the first security domain comprises a high side of a blockchain network and the second security domain comprises a low side of the blockchain network.

13. The method of claim 9 , wherein cross-domain security policy identifies data which cannot pass from the first security domain to the second security domain.

14. The method of claim 9 , wherein the cross-domain security policy identifies data which is allowed for storage in the first and second security domains.

15. The method of claim 9 , further comprising verifying that sensitive channel membership information of the first security domain is not included within the gossip message prior to transmitting the updated gossip message to the second domain anchor peer.

16. The method of claim 9 , further comprising receiving a request to transmit the gossip message from the domain anchor peer in the second security domain, and transmitting the request to the domain anchor peer in the first security domain.

17. A non-transitory computer readable medium comprising instructions, that when read by a processor, cause the processor to perform a method comprising:

establishing a first communication channel between an anchor peer in a first security domain and a multi-domain relay and a second communication channel between an anchor peer in a second security domain and the multi-domain relay, wherein the first and second security domains are logically isolated from each other and share a blockchain ledger;

receiving a gossip message originated from the anchor peer in the first security domain, wherein the gossip message comprises block content from the blockchain ledger;

verifying, via the multi-domain relay, that block content within the gossip message does not violate a cross-domain security policy of the first and second domains;

in response to verifying the block content, updating an endpoint of the gossip message with an address of the anchor peer in the second security domain; and

transmitting the updated gossip message to the anchor peer in the second security domain.

18. The non-transitory computer-readable medium of claim 17 , wherein the updating comprises replacing an address of the anchor peer in the first security domain with the address of the anchor peer in the second security domain within the gossip message, prior to transmitting the updated gossip message to the anchor peer in the second security domain.

19. The non-transitory computer-readable medium of claim 17 , wherein the block content comprises block hashes, block numbers, and transaction data stored on an instance of the blockchain ledger of the anchor peer in the first security domain.

20. The non-transitory computer-readable medium of claim 17 , wherein the first security domain comprises a high side of a blockchain network and the second security domain comprises a low side of the blockchain network.