Search method using data structure for supporting multiple search in blockchain-based IoT environment, and device according to method

1. A method for providing a search function for blockchain, comprising:

receiving block data via a network;

verifying transactions included in the received block data; and

adding the block data as a node to an index tree of multidimensional index structures based on information about each transaction in the transaction verification, wherein the index tree of multidimensional index structures is a balanced tree including nodes of a uniform size that is equal to a disk page size, each node is stored in a page, an internal node is responsible for one region in a multidimensional space, a leaf node stores data page information, transaction data is located in a search space along an index node indicating a space to which each transaction data belongs, and wherein in the index tree of multidimensional index structures a search key is a plurality of fields according to Point Access Method (PAM).

2. The method for providing a search function for blockchain according to claim 1 , wherein, in the index tree of multidimensional index structures, the transaction data comprises multidimensional points and is stored in a disk.

3. The method for providing a search function for blockchain according to claim 1 , further comprising:

updating ‘Mempool’ that stores unconfirmed transactions, in the transaction verification.

4. The method for providing a search function for blockchain according to claim 1 , further comprising:

after the transaction verification is completed, calculating ‘Merkle Root’ based on transaction information, and verifying a block header.

5. The method for providing a search function for blockchain according to claim 1 , further comprising:

storing the transaction verified block data in a local disk.

6. A non-transitory, computer-readable recording medium having recorded thereon a program that, when executed by at least one processor, causes the at least one processor to perform the method according to claim 1 .

7. A method for providing a search function for blockchain, comprising:

receiving, by a receiver, block data according to multidimensional index structures from a sender via a network;

verifying, by the receiver, transactions included in the received block data; and

adding, by the receiver, the block data as a node to an index tree of multidimensional index structures based on information about each transaction in the transaction verification,

wherein the received block data includes a first hash value generated from information about the number of nodes stored in the sender's index tree according to the multidimensional index structures, and wherein the index tree of multidimensional index structures is a balanced tree including nodes of a uniform size that is equal to a disk page size, and is a K-dimensional B-tree (K-D-B Tree), and wherein in the index tree of multidimensional index structures a search key is a plurality of fields according to Point Access Method (PAM).

8. The method for providing a search function for blockchain according to claim 7 , wherein in the index tree of multidimensional index structures transaction data comprises multidimensional points and is stored in a disk.

9. The method for providing a search function for blockchain according to claim 7 , further comprising:

calculating, by the receiver, the number of internal nodes stored in the receiver's index tree additionally created after the transaction verification is completed and generating a second hash value from it; and

verifying, by the receiver, integrity by comparing the first hash value included in the block data received from the sender and the second hash value generated by the receiver.

10. The method for providing a search function for blockchain according to claim 9 , wherein each of the first hash value and the second hash value is calculated using information about an index tree created until a previous block, ‘Merkle Root’ for ensuring integrity of transaction information in a currently inputted block data, and the number of nodes after creating an index tree through the currently inputted block data.

11. The method for providing a search function for blockchain according to claim 9 , further comprising:

when the integrity verification succeeds,

verifying, by the receiver, a block header; and

propagating, by the receiver, the block data to other user.

12. The method for providing a search function for blockchain according to claim 7 , further comprising:

after the transaction verification is completed,

calculating ‘Merkle Root’ based on transaction information.

13. A user device for blockchain, comprising:

a processing unit comprising at least one processor communicatively coupled to a memory, the processing unit communicatively coupled to a communication unit and a storage unit, wherein:

the communication unit transmits and receives block data via a network;

the processing unit verifies transactions included in the block data received through the communication unit, and adds the block data as a node to an index tree of multidimensional index structures based on information about each transaction in the transaction verification, wherein the index tree of multidimensional index structures is a balanced tree including nodes of a uniform size that is equal to a disk page size, and is a K-dimensional B-tree (K-D-B Tree), and wherein in the index tree of multidimensional index structures a search key is a plurality of fields according to Point Access Method (PAM); and

the storage unit stores the index tree and the block data.

14. The user device according to claim 13 , wherein in the index tree of multidimensional index structures transaction data comprises multidimensional points and is stored in a disk.

15. The user device according to claim 13 , wherein the block data received through the communication unit includes a first hash value generated from information about the number of nodes stored in a sender's index tree according to the multidimensional index structures, and

the processing unit:

calculates the number of internal nodes stored in its index tree additionally created after the transaction verification is completed, and generate a second hash value from it, and

verifies integrity by comparing the first hash value included in the block data received from the sender and the generated second hash value.

16. The user device according to claim 15 , wherein each of the first hash value and the second hash value is calculated using information about an index tree created until a previous block, ‘Merkle Root’ for ensuring integrity of transaction information in a currently inputted block data, and the number of nodes after creating an index tree through the currently inputted block data.

17. The user device according to claim 15 , wherein when the integrity verification succeeds,

the processing unit:

verifies a block header, and

propagates the block data to other user.