With the rapid development of digitization technology, digital copyright of museum has become more and more valuable. Its collections can be opened to and shared with the people through the Internet. However, centralized authorization, untransparent transaction information and risk of tampering data in traditional digital rights management have a strong impact on system normal operation. In this paper, we proposed a blockchain-based digital rights management scheme (BMDRM) that realizes a distributed digital rights management and authorization system by introducing non-fungible tokens (NFTs) and smart contracts. To ensure the security and efficiency of transactions and authorization, we store all processing data in a high-security distributed ledger based on cryptographic signatures. We test our scheme on Ethereum private network and the experimental results show that BMDRM is feasible and secure for digital rights management in museums.
Museum has a wealth of cultural heritage for display, research, education and dissemination of human history. These cultural relics can be transformed into text, image and video through digital scanners and cameras which are considered as copyrighted digital files finally. With the rapid development of museum digitization and application of related digital technologies, museum digital data is constantly becoming more valuable and convenient for people to feel the charm of cultural relics in digital museums. Although the digitization of cultural relic assets has brought new vitality to museums, it is also facing great challenges in sharing and disseminating digital copyright through Internet securely [
Reasonable digital rights management (DRM) technology has been a hot issue in academic and industrial research. Chen [
In order to solve the reliable and efficient operation of digital rights management, in this paper, we proposed a blockchain-based digital rights management scheme (BMDRM), we introduced non-fungible tokens (NFT) to realize distributed digital rights issuance. Authentication, ownership and authorization information can be stored in smart contracts through NFT and smart contracts can make transaction and issue authorized digital rights automatically. There are two main types of tokens used in smart contracts: Fungible tokens (FTs) and Non-Fungible Tokens (NFTs). Their differences depend on the asset they represent. FTs can be used as the base currency for copyright transactions and licensing. In the digital copyright mechanism, museums can express their ownership of cultural relic copyrights by creating NFTs and applicants can purchase authorized NFTs through FT to obtain authorization certificates.
The main contributions of this paper are the following:
(1) We proposed a scheme (
(2)
(3) We compared our scheme with others in public authentication, traceable, decentralization and gas cost, the results show that BMDRM can effectively improve security and flexibility of digital rights management in museums.
The rest of this article is organized as follows. Section 2 provides background of the research. Section 3 deals with the proposed museum-digital rights management mechanism. Section 4 presents an analysis of the proposed scheme. In Section 5, the discussions and comparisons are given. Finally, we conclude this study.
Blockchain is defined as a distributed shared digital ledger for transactions. It applied public key cryptography to ensure the identity and pseudo-anonymity of all participants and decentralized consensus algorithms to maintain the ledger and verify any transaction. Ethereum [
In the blockchain domain, a token can be used to represent some crypto-currencies, such as Bitcoin or Ether [
In this study, we use ECDSA [
(1) Applicant(A) —— Citizens or institutions who want to access the digital content resource of the museum and buy authorization NFT and Mt token by smart contract.
(2) Museum (M) —— The museum is the owner of the digital content. They send classified digital content resource to content center and content center sends back a copyright NFT which represents the ownership of the digital content.
(3) Content Center (CC) —— Content Center is the manager of smart contract that can create NFTs and FTs. Content Center accepts the parties’ registration and sends public/private key pair to each party.
(4) Bank (B) —— The applicant pays for MT tokens to content center via bank.
We briefly illustrate the scenarios in the following steps:
Setp 1: System initialization
Applicant, museum, and content center need to register in the blockchain and get their public/private key and blockchain account (BCA). Applicant and museum also get identity certificate and public/private key pair from the content center which deployed smart contracts for creating token and decentralized trade.
Setp 2: Copyright NFT production phase
The museum will upload the sorted digital resources to the digital content center and the digital content center will encrypt the content into protected digital resources. Then content center will store them in IPFS and send the unique identifier of the NFT to the data owner.
Setp 3: Fungible Token purchase phase
The applicant can buy tokens from the digital content center. When content center verified the money from the applicant via bank, content center will send MT tokens to the applicant's address.
Setp 4: Authorization Token purchase phase
The applicant can purchase authorizations from the digital content center and use tokens to pay authorization fees through smart contracts. The smart contract will automatically send the Authorization NFT to the applicant's address if the account has enough tokens.
Setp 5: Digital content browsing phase
The applicant submits its authorized NFT to the content service provider and accesses the protected digital content in an authorization policy
The NFT-based smart contract was developed by Solidity. In the proposed architecture, we use smart contract functions to implement a transaction platform. The main functions are described as below:
Museum, applicant and content center register in the blockchain to obtain the public key and private key pair. Meanwhile applicant and museum apply for identification
Setp 1: The private key address is mapped into a 64-byte public key by the elliptic curve algorithm (ecdsa-secp256k1).
Setp 2: Algorithm keccak-256 is used to hash the public key and convert the public key into 32 bytes.
Setp 3: The last 20 bytes of the hashed public key serves as the account address
The digital content center deployed smart contracts on the blockchain to obtain addresses and management rights. At the same time, Content center call the constructor function to obtain the supply of the museum token. The museum token can be transferred to any account through the smart contract. Applicant and museum can apply for exchange of the museum token and use MT token to pay the fee of authorization and copyright NFT. The description of MT token is shown in the
Item | Information |
---|---|
Token name | Museum token |
Symbol | MT |
Total supply | 1000000000 |
Decimal | 8 |
Contract address | 0x5B38Da6a701c568545dCfcB03FcB875f56beddC4 |
An applicant can purchase MT tokens from the content center to pay the authorization fee. The applicant transfers
Setp 1 Applicant generates a random value
And applicant will send
Sept 2 Content center first decrypt the encrypted data by private key and obtain the information
If the verification is passed, content center will upload signature into the blockchain and get transaction information (
Setp 1: Then content center generates a random value
And content center will send
Setp 2: Applicant decrypts the encrypted data by private key and obtains the information (
Applicant will upload signature into the blockchain.
Museum institutions collect a large number of collections that can be converted into digital content, such as calligraphy and painting. Museum transforms these contents into digital content files and publishes them as NFT through content center. Since blockchain is not suitable for storing large files (video, audio, e.g.), we store digital files on IPFS. We will introduce the process of creating the NFT digital content shown in
Step 1: Museum first classifies their digital contents and uploads digital contents with information of museum address and public key to content center. Then content center will return a unique identity
Step 2: Content center encrypts the digital content and uploads the encrypted file to IPFS which will return digital content hash value
The detail of Copyright NFT production phase are shown as follow:
Setp 1: Museum generates a random value
And museum sends
Step 2: Content center first decrypts the encrypted data by private key and obtains the information (
If the verification is passed, content center uploads signature into blockchain and gets digital file information uploaded by the museum (
Item | Information |
---|---|
Token ID | A unique identifier of the token |
CID | ID of digital content |
Resource URI | A string representing the resource to be accessed |
Owner | The address of owner |
PK | The public key of owner |
ID | The ID of owner |
Timestamp | Create time of the NFT |
Price | Price of a day |
Then content center generates a random value
And content center sends
Then museum first decrypts the encrypted data by private key and obtains the information
Museum will upload signature into the blockchain.
An applicant can obtain the token ID and price of a copyright NFT when browsing the contents in the copyright NFT market and calculate the payment for the authorization by:
After purchasing MT tokens from content center, the applicant can call the smart contract function
If the balance of the applicant's MT token is greater than or equal to the payment, the authorization NFT will be sent to the applicant and the payment will be transferred to the owner address of the copyright NFT. Otherwise the transaction will be canceled. Algorithm 1 introduces the process of buying authorization NFT:
After the authorization NFT is paid, the applicant blockchain address will receive an authorization NFT sent by
Item | Information |
---|---|
TokenID | A unique identifier of the token |
CID | A ID of digital content |
Right_token | Token id of copyright token. |
Owner | The address of owner |
PK | The public key of owner |
ID | The ID of owner |
Timestamp | Create time of the NFT |
Validity period | Validity period of authorization |
After purchasing the authorization NFT through smart contract, applicant can provide it to content service provider for access digital content stored in IPFS. In our scheme, we use Authorization NFT and ID as access control of the digital content. The applicant commits
Content center first verifies whether the identifier is valid by comparing
If the applicant request is valid, content center will query authorization information by
Then content center agent checks whether the access control policy is satisfied
Content center provides the digital content to the applicant if
Our scheme mainly has two parts of authentication process: (1) the purchase of transaction tokens and the creation of copyright NFTs, (2) the automated trade on the blockchain. In off-chain situation, sender signs the message with ECDSA and receiver verifies the correctness of the message. All signature information will be uploaded to the blockchain. Each newly generated block is a verification of previous block data. When using smart contract transactions on the blockchain, participants initiate transactions through their own blockchain accounts (BCA) and each transaction is stored in the blockchain with a transaction hash. Subsequent transactions will also verify correctness of previous transactions.
Once the digital content of museum is uploaded on the blockchain, copyright information is stored as NFT on the blockchain permanently and cannot be tampered. And all authorization and authentication transaction generated by smart contract are stored on the blockchain. We can query the issuance record of authorized NFT as a digital certificate in preventing torts on preventing loss from extending.
There are three advantages of the digital right management scheme proposed in this paper: (1) digital NFT is stored on the distributed storage system (IPFS). (2) all transactions are stored on the blockchain. (3) the trading platform uses smart contracts without participation of a third party. It is safer, applicable and convenience because of precluding a single point of failure in system.
Most of the smart contracts that run in the Ethereum are programed by Solidity and every line of code in Solidity requires a certain amount of gas to be executed. It depends on the priority and size of the transaction and computational cost of the function. The gas consumption of function is shown in
Function | Gas consumption |
---|---|
1947639 | |
52758 | |
296706 | |
169551 | |
241704 |
We write smart contracts by solidity and tested the function in Ethereum private network by Remix [
As shown in
Method | Description | Blockchain |
Authentication | Traceable | Cash flow | NFT support | Automatic transaction |
---|---|---|---|---|---|---|---|
Zhao et al. [ |
Combined digital watermarking technology in digital rights management system | ||||||
Ma et al. [ |
Blockchain based DRM with efficient and secure authentication, privacy protection | Y | Y | N | N | N | N |
Ma et al. [ |
Blockchain based DRM platform with high-level credit and security | Y | Y | Y | N | N | N |
Lu et al. [ |
A scheme for digital rights management for design works. | Y | N | Y | N | N | N |
Wang et al. [ |
An authorization of the museum’s collections. | Y | Y | Y | Y | N | N |
Ours | Blockchain based museum-digital right platform with NFT and FT | Y | Y | Y | Y | Y | Y |
The digitization and decentralized trade platform of museum provided great help for culture dissemination and economic benefits. We propose a museum digital asset management mechanism based on smart contract, FT and NFT. This mechanism is used for decentralized trading of museum digital assets. MT tokens is the circulating currency of the trade platform and copyright and authorization NFT provide certificates of digital assets. We made a detailed analysis of the data and cash flow interact with blockchain and tested the functions on the decentralized trading platform. The case study demonstrated the feasibility of the proposed framework in museum digital right management. For future work, we plan to explore more areas in which we can use NFT to track entities in the world and design more detailed control policy with securer encryption technology.
The authors gratefully acknowledge the experiment suggestions from lab mates. The authors are also grateful to the anonymous referees for their insightful comments and suggestions.
A
Finite group
The elliptic curve defined on finite group
A generating point based on the elliptic curve
A random value on the elliptic curve
Elliptic curve signature value of
An ECCDSA signature message of
An identity of
A blockchain address of
Encrypted message using key of
A digital certificate of
An authentication of
Hash function