Next generation blockchain-type database

bitFlyer's original blockchain "miyabi" – the fastest in the world1, having achieved 2,000 transactions per second, using an independently developed consensus algorithm, and with a robust and high-speed smart contract execution engine for the ultimate in performance – independently developed consensus algorithm has taken a new and historic step.

1 Based on our research

About “miyabi”

Since our inception, bitFlyer has been dedicated to researching the potential of practical implementation of immutable, highly reliable blockchain technology for uses including actual transactions and smart contracts. Blockchains modeled upon PoW (Proof of Work) or PoS (Proof of Stake) have always had the major problem of not being able to trust the data (finality) due to block divergence or “isolated blocks” resulting from processes like a “hard fork.” “miyabi” was designed to always guarantee finality using a unique consensus algorithm.

“miyabi” is the world’s fastest blockchain technology (* based on our research), maintaining the durability blockchains are known for, while solving problems such as transaction settlement and slow processing speeds. With a system constructed specifically for enterprise, our “miyabi” private blockchain provides a great number of benefits to users.

Difference between “miyabi” and other databases
Centralized DB
Key Value
Object Oriented
Graph Oriented
Distributed Database 
Apache Cassandra
DLT+ Immutability
R3CEV Corda
(Wide Sense) Blockchain+ BFT
Blockchain- Single Point of Failure (SPOF)
Public blockchain
No Finality
Private Chain
Private Chain
Hyperledger Fabric
Blockchain performance comparison
  •  Bitcoin: 2 transactions/sec
  •  Ethereum: 7 transactions/sec
  •  Leading competitor: Around 1,000 transactions/sec
  • miyabi: 1,500 - 2,000 transactions/sec2With top of the line hardware 4,000+ transactions/sec


  • miyabi offers an extremely high level of security not available in normal database systems.
  • The data for each transaction is stored in a block, and a hash of the data in each block is stored in the next block, creating a chain of dependency between the blocks.
  • Chaining together the blocks in this way allows the consistency of the transaction data to be guaranteed. It is easy to detect when transaction data is overwritten, and this is believed to make data tampering effectively impossible.


  • miyabi allows for the securing of transactional finality in which the data for each transaction can be fully confirmed.
  • One major problem with blockchains such as those used in Bitcoin and Ethereum is that the data stored therein is not permanently fixed. In a Bitcoin-style blockchain, the probability of existing data being overwritten decreases as time passes.
  • However, miyabi's algorithm is written in such a way that data cannot be altered or lost as soon as it is written.

Byzantine Fault Tolerance (BFT)

  • miyabi is a pure blockchain with Byzantine fault tolerance (BFT).
  • Nodes (servers) that do not behave properly, whether due to hardware issues, hacking or other causes, are known as Byzantine nodes.
  • A blockchain with Byzantine fault tolerance remains able to function properly as long as the number of Byzantine nodes does not exceed a certain amount. Older systems did not feature Byzantine fault tolerance, and the entire system would go down if even one server stopped working. Measures such as triple modular redundancy are used to help prevent such occurrences, but this does not completely protect from hacking.

Single Point of Failure

  • miyabi does not require a certificate authority. A certificate authority is a single point of failure, and a technical issue or an incident such as a DDoS attack at the certificate authority poses the risk of taking the entire blockchain down. Even if redundancy measures are implemented at the certificate authority, this does not change that fact that it is a single point of trust (SPOT). With miyabi, privilege setting is done with a secret key, eliminating the weaknesses present with a single point of failure and a single point of trust.

Smart Contract

  • miyabi's "Kotowari" isolated execution engine quickly and robustly executes smart contracts. Standard support is also provided for escrow contracts. It is possible to safely exchange multiple assets simultaneously, and the time-stamped contracts are non-tamperable.

Disaster countermeasures (High Availability)

  • miyabi offers high availability even in the face of disasters. Even in the event that a subset of the servers (nodes) are lost due to a disaster, all of the data is stored in each node, and it remains possible to access the latest correct data. For example, an approach of maintaining servers in a variety of locations such as Japan, the United States and Europe allows for a flexible system that is highly disaster-resistant.

Performance (Throughput)

  • miyabi is able to process 2,000 transactions per second (4,000 transactions per second on advanced hardware) and boasts the world's highest performance (according to a study performed by this company) of any finality-ensured blockchain.
  • Existing blockchain technologies have struggled with the issue of extremely slow processing speeds.
  • It is its support for finality and BFT, its elimination of the single point of failure (SPOF) and its high performance (throughput) that give miyabi its technological superiority.


  • At one to four seconds, miyabi features shorter delays than other blockchain products (Ethereum has a 12-second delay and does not ensure finality).
  • A blockchain is a type of distributed database. What we consider a blockchain is a system that includes a new database with features such as non-tamperability, finality and Byzantine fault tolerance as well as a smart contract execution environment. Since the nodes and data are distributed over the network, the processing speed, including the throughput and delay, depends greatly on the speed of the network.