How do you pronounce Metadium?
What problems can Metadium solve?
What are PKI and dPKI? How do you plan to decentralize the PKI?
• Certificate issuance system and method based on blockchain
This patent will be utilized in Metadium’s dPKI to replace traditional Certificate Authority (CA) and to store certificates on blockchain. Key element of the PKI system is a CA that assures individual certificates and the public / private key of each individual. CA is an institution that can manage and guarantee transaction records in accordance with the Electronic Signature Act, and can establish and securely manage authentication system. Therefore, CA must be trusted by all users as CA verifies the authenticity of the user's personal information using the private key and proves ownership of the public key provided by the user. In Metadium, trustlessness of the blockchain technology will replace CA. In addition, privacy problem does not occur even if the certificate is stored in the public blockchain as certificate is stored on a blockchain with a hashed value of personal information in the certificate.
• Managing private key in a PUF (Physical Unclonable Function)
This patent addresses on how to generate a private key with high entropy and proceed with authentication in a hardware device while eliminating private key leakage problem. The private key is a random length of bits (e.g. 512 bits in ecdsa256). The private key must be created in a situation where the entropy is as high as possible to guarantee the maximum safety. One of the biggest problems with the widely used PKI systems is that it is difficult for a user to securely store a private key. The role of the private key is to create a signature, which is not a physically memorable value for the user and should not be moved outside the generated terminal. If a private key is generated and managed utilizing PUF, it is possible to prevent a private key from being leaked out to other parties.
• Method to utilize certificate information through biometrics
This patent addresses methods to utilize private key with biometric information of a user. It is impossible to directly input private key in order to allow the operation of the private key to generate the signature in the PKI system. Therefore, user utilizes private key with a pre-generated password to decrypt the encrypted private key. However, passwords are easily leaked and the more passwords the user has to remember, the more problems they can cause. As the use of personal terminals becomes common, accessing services using the biometric authentication information (ex. fingerprint touch ID) without using a password is becoming common. Metadium platform allows access and manage of private key with the use of individual’s biometric information.
• Method for providing certificate service based on multiple signatures
From a service perspective, different approaches in accessing certificate must be possible depending on the use of the certificate. Currently, the authorized certificate distinguishes only the conditions under which a specific user can use the authorized certificate. Therefore, the system does not support the use of multiple signature-based certificates, where use of certificate can be possible when two or more parties authorize the use of certificate with the pre-registered public key through a consensus. This patent addresses the multi-signature certificate technology that provides a function of registering several public keys in a certificate, to make various use cases including recovering Meta ID even when a private key is lost.
• Method for providing certificate service based on smart contract
Current certificate has a condition that certificates can be used only in specific cases such as bank, insurance, securities, etc. It does not have the function of conditional-availability of the certificate (ex, proof of third party, limits on use, date and weather conditions). In this patent, smart contract which operates in a decentralized way without administrator's intervention, writes and records the execution conditions of the certificate in code form, and deals with the smart contract based certificate that is automatically executed according to the user's action.
• Method for certifying a user through blockchain and Merkle tree structure
When storing a certificate in a blockchain, it is not safe to store private information because all the data stored in the blockchain is accessible. Though hash value of personal information are encrypted, privacy is not guaranteed as disclosing all original data that generated the hash value is necessary to verify authenticity of the hashed information. For this reason, personal information is processed using the Merkle tree and the root hash (that is the final value of the Merkle tree) is stored in the blockchain. In this case, users can disclose only the desired information to the subject. The authenticity can be verified by using the root hash value on the blockchain. It is also possible to disclose parts of information without disclosing entire information using the hierarchy structure of the Merkle tree. For example, to disclose the city users live in, users can disclose ‘Seoul’ rather than disclosing the full address.
What are the Patents that are going to be used for Metadium?
Identity blockchain refers to a system in which all CRUD operations (create, read, update, delete) and the use of IDs are controlled by ID owners, and all actions related to IDs are stored in the form of transactions in the blockchain.
What is Identity Blockchain?
Yes, there are transaction fees to prevent DDoS (Distributed Denial of Service) attacks. In a DDoS attack, an attacker tries to flood the network with dummy transactions. If the attacker has to pay a sufficiently high fee for each of those dummy transactions, this form of attack will become too expensive to carry out.
Are there transaction fees on Metadium Blockchain?
Self-Sovereign Identity refers to the concept that individuals have the ability to control their own identity. Blockchain will store a unique identifier and a proof of verification, while all of the user data is securely saved on the user’s personal device, fully controlled by the user.
As the term “self-sovereign” indicates that individuals verify their own personal information, individuals become the verifier. In the Metadium blockchain, users can verify their personal information of their Meta ID to upload their information.
Meta ID can be used only through a private key that users register in advance. Users can register many different keys in the Meta ID contract. With these keys, and the Meta ID as their identity, individuals can participate in the Metadium blockchain.
What is self-sovereign identity and how do you manage it on blockchain?
In the present day, our personal identity is not managed by ourselves. Instead, they are stored in the servers of the service providers whom, as a matter of fact, came to own them. In this way, users were unable to track how and where their personal information is being used, and were threatened by black marketeers who buy and sell these information without our notice. This is an inevitable weakness in existing underlying identity schemes. Metadium resolves this through a Decentralized ID (DID) using a Metadium blockchain.
What is the current status on personal identity management?
Yes. On the Ethereum blockchain, there is a Metadium ERC-20 contract that implements ERC-20 standard with a few modifications for some operations. We have plans to freeze the token along with our launch of the Metadium Mainnet. Then you can swap your Metadium ERC-20 token on the Ethereum mainnet to the ‘META’ - the native coin of Metadium - on the Metadium mainnet.
What is Proof of Authority (PoA)?
PoA is a method in which nodes that have been previously agreed generate blocks in turn (not just round-robin, but it can be shuffled.) Metadium uses the Raft algorithm to select the leader that generates the block. Since we have decided to trust these block producers in PoA, we do not use the mining processes that are used in PoW. As a result, new blocks are often said to be “forged” instead of “mined”.
In PoW, nobody can trust each other, so we gain trust through mining. In the mining process, we use a lot of resources such as the CPU, memory, and the electricity. Also, it is difficult to have more than two digit tps in terms of performance.
PoS is a method designed to overcome the shortfalls of the PoW. Instead of mining, the “stake” that depends on the user’s wealth in the network determines the level of authority to produce and verify the blocks. However, the PoS method requires users to stake their assets in order to produce or validate blocks, and there’s also the added problem of having “nothing at stake”. Ethereum tries to resolve this by introducing the casper and slashing condition.
In PoA, predefined nodes carry out the service. There is no problem of wasting monumental resources related to mining in PoW, and there is no need to stake the user’s assets as in the PoS. Although one can point out that the PoA method is centralized, the number of nodes participating in the PoA can be substantially extended. The network maintenance and performance also far exceeds the PoW/PoS methods.
Metadium uses a consensus algorithm based on PoA with Raft. Each node participating in the PoA can have something similar to a “governance token” by staking the META token, and each node has the power to participate in the metadata network according to its governance token. Governance token is used in voting procedures to decide the addition or removal of PoA participating nodes, forking, and the reserve pool management. The voting power is proportional to the amount of governance token. An additional governance token can be secured by staking additional META tokens, and all of the governance tokens are incinerated when attempting to suspend activity with a PoA node.
What are the advantages of PoA over PoW or PoS?
The RAFT algorithm is a distributed processing system whereby distributed nodes agree on each other. The RAFT system is mainly divided into a 1) Leader Election and 2), Follow Leader (Log Replication). This leads to the consensus among distributed nodes. The node that receives a majority vote from other nodes through real time voting assumes the leader position. Followers then agree to update their data according to the leader. The most popular algorithm in distributed processing is Paxos, whereby an easy-to-understand version of Paxos is RAFT.
If we try to understand DPoS in the perspective of RAFT, the procedure would be as follows: 1) a block producer (leader) is elected, 2) it generates a block, 3) propagates to the network, and 4) the leader changes. Metadium uses the "etcd" which is one of the "Go-implementations" of the Raft consensus, which is a mixture of PoA and DPoS. Voters can add or exclude block producers on the network.
Here is a friendly explanation of the RAFT consensus. :
What is RAFT consensus algorithm?
With respect to mining, since Metadium uses a consensus method that combines PoA and Raft, a fork is less likely to occur than other blockchain platforms adopting a PoW method. However, a fork can happen, and in this case, we select the longest chain. Even if a particular node generates a fork as a result of a misbehavior, the network will function normally if the majority behaves properly.
In terms of non-fork protocols related to block production, a Metadium blockchain can generate fork under the agreement of network participants. When a specific issue that might need a fork arises, participants can judge the importance of the issue and decide whether to hard fork or soft fork. These processes will be open to all and proceed in a transparent and rational manner. As with many platforms, including Ethereum, which has experienced the DAO situation, it is not easy for platforms to run perfectly from the beginning. The Metadium platform also has the potential for a fork.
How can you protect from data leak and hacking attempts using Meta ID?
How do you guarantee the total control over the Meta ID?
How can you optimally manage, use & protect user’s personal identity on blockchain?