Computer-implemented systems and methods for implementing transfers over a blockchain network
The invention provides improved verification solutions for blockchain-implemented transfers. It is suited for, but not limited to, implementation in an SPV wallet. In accordance with one embodiment, a system or resource is provided which comprises a plurality of novel SPV verification components, the activities of which are coordinated by a coordination component. The system enables Bob to send Alice a payment transaction template (template Tx3) and requests: the full transaction data for all input transactions (Tx1, Tx2) comprising at least one output that Alice wants to spend as inputs to a transfer (Tx3); the Merkle path for all input transactions (Tx1, Tx2) linking them to their respective Merkle roots associated with their respective block headers; the completed transfer transaction (Tx3). Alice provides this information plus her signature. Bob can then perform local SPV checks on the input transactions Tx1, Tx2 using transactions Tx1 and Tx2, their corresponding Merkle paths Path 1, Path 2, and Bob's local list of block headers. Bob broadcasts the transfer transaction (Tx3) to the P2P network.
1. A computer-based system operative to use Simplified Payment Verification to facilitate a blockchain transfer of an asset over a blockchain network between a transferor and a transferee, comprising:
i) a plurality of verification resources; and
ii) a coordination component operative to communicate with the at least one verification resource and select the at least one verification resource from the plurality of verification resources;
and wherein the at least one verification resource is arranged to:
a) receive using an off-chain communication that does not involve the blockchain or blockchain network:
1) complete transaction data relating to at least one input blockchain transaction (Tx1) that comprises at least one output that spends to an input of a transfer transaction (Tx3); and
2) a Merkle path for the at least one input blockchain transaction (Tx1);
b) perform a Simplified Payment Verification check on the at least one input blockchain transaction (Tx1) using the complete transaction data and the Merkle path to prove that the input transaction (Tx1) that comprises the at least one output that spends to the input of the transfer transaction (Tx3) is valid and in the blockchain, and wherein the Simplified Payment verification check is performed locally on the at least one verification resource and does not go through the blockchain network; and
c) determine that the Simplified Payment Verification check proves that the input transaction is valid and in the blockchain; and
d) responsive to determining that the Simplified Payment Verification check proves that the input transaction (Tx1) is valid and in the blockchain, transmit the transfer transaction (Tx3) to the blockchain network for mining into a block on the blockchain to transfer the asset from the transferor to the transferee over the blockchain.
2. The computer-based system of claim 1 , wherein at least one verification resource in the plurality of verification resources comprises at least one public key that is associated with a private key, and wherein the private key is provided:
in the at least one verification resource; or
in the coordination component.
3. The computer-based system of claim 1 , wherein the verification resource is operative to at least one of:
verify whether a specified transaction is stored on a blockchain; or
facilitate or enable a transfer from one address to another using a blockchain transaction.
4. The computer-based system of claim 1 , wherein the coordination component is operative to cause the at least one verification resource to at least one of:
verify whether a specified transaction is stored on a blockchain; or
facilitate or enable a transfer from one address to another using a blockchain transaction.
5. The computer-based system of claim 1 , wherein the coordination component is operative to send and receive transaction related data to and from a blockchain network.
6. The computer-based system of claim 1 , wherein the coordination component is operative to:
send and receive at least one of at least one public key or transaction ID (TXID) to and from the at least one verification resource.
7. The computer-based system of claim 2 , wherein the private key is a seed.
8. The computer-based system of claim 1 , wherein each of the plurality of verification resources-comprises at least one public key associated with a respective private key.
9. The computer-based system of claim 1 , wherein the at least one verification resource is operative to:
i) use the Merkle path to verify a Merkle proof for the at least one transaction; or
ii) store, receive and/or request at least one block header of a blockchain transaction.
10. The computer-based system of claim 1 , wherein the complete transaction data or Merkle path are received and/or requested from a providing resource which is the transferor of the asset and is operative to store and/or send:
i) complete transaction data relating to the at least one blockchain transaction; and
ii) the Merkle path of the at least one blockchain transaction.
11. The computer-based system of claim 10 , wherein at least one of the providing resource or the verification resource is or comprises at least one of:
a digital wallet, a cryptocurrency wallet, a Simplified Payment Verification Wallet or a smart card.
12. The computer-based system of claim 1 , wherein the computer-based system is operative to receive transfer data from a providing resource which is the transferor of the asset, the transfer data comprising at least one of:
data relating to at least one unspent transaction output (UTXO) stored on a blockchain;
a transaction ID (TXID) for a transaction containing the at least one unspent blockchain transaction output (UTXO);
a signature for spending the at least one unspent blockchain transaction output (UTXO);
a Merkle path for a transaction containing the at least one unspent blockchain transaction output (UTXO); or
a public key address.
13. The computer-based system of claim 1 , wherein the system is operative to at least one of:
i) send at least one of a transfer value or an output address to a providing resource;
ii) receive at least one of a transfer value or an output address from a providing resource which is the transferor of the asset; or
iii) submit a transaction to the blockchain network upon successful verification of the Merkle proof for the at least one blockchain transaction.
14. The computer-based system of claim 1 , wherein the system is operative to send, to a providing resource which is the transferor of the asset, a request for transfer data comprising at least one of:
data relating to at least one unspent transaction output (UTXO) stored on a blockchain;
a transaction ID (TXID) for a transaction containing the at least one unspent blockchain transaction output (UTXO);
a signature for spending at the at least one unspent blockchain transaction output (UTXO);
a Merkle path for a transaction containing the at least one unspent blockchain transaction output (UTXO); or
a public key address.
15. The computer-based system of claim 14 , wherein the transfer data is requested by the system, and/or received from the providing resource, using a blockchain transaction template.
16. A method to facilitate a blockchain transfer of an asset over a blockchain network between a transferor and a transferee, comprising:
using an off-chain communication that does not involve the blockchain or blockchain network to receive or request, by at least one verification resource in a plurality of verification resources, the at least one verification resource comprising at least one public key:
complete transaction data relating to at least one blockchain transaction (Tx1) that comprises at least one output that spends to an input of a transfer transaction (Tx3), and
a Merkle path for the at least one blockchain transaction (Tx1),
performing, by the at least one verification resource, a local Simplified Payment Verification check on the at least one input blockchain transaction (Tx1) using the complete transaction data and the Merkle path to prove that the input transaction (Tx1) that comprises the at least one output that spends to the input of the transfer transaction (Tx3) is valid and in the blockchain, and wherein the Simplified Payment verification check is performed locally on the at least one verification resource and does not go through the blockchain network; and
if the Simplified Payment Verification check is proves that the input transaction is valid and in the blockchain, submitting the transfer transaction (Tx3) to the blockchain network for mining into a block on the blockchain to transfer the asset from the transferor to the transferee over the blockchain;
wherein:
a private key is associated with the at least one public key; and
a coordination component is configured to communicate with the at least one verification resource and to select the at least one verification resource from the plurality of verification resources.
17. The method of claim 16 , wherein the private key is provided in the at least one verification resource or in the coordination component.
18. The method of claim 16 , wherein the verification resource is configured to at least one of verify whether a specified transaction is stored on a blockchain or facilitate or enable a transfer from one address to another using a blockchain transaction.
19. The method of claim 16 , the coordination component is operative to cause the at least one verification resource to at least one of:
verify whether a specified transaction is stored on a blockchain or facilitate or
enable a transfer from one address to another using a blockchain transaction.
20. The method of claim 16 , wherein the coordination component is operative to send and receive transaction related data to and from the blockchain network.