Blockchain technology, while revolutionary, has faced significant challenges in scalability, security, and energy efficiency. Previous blockchain projects, such as Bitcoin and Ethereum, have struggled to meet the growing demands of decentralized applications. Harmony, a next-generation blockchain platform, aims to address these challenges by combining cutting-edge research and engineering practices to create a scalable, secure, and energy-efficient blockchain infrastructure.
Harmony’s innovative use of state sharding, adaptive consensus protocol, and efficient networking solutions make it a highly scalable and secure blockchain platform that has the potential to revolutionize decentralized applications and overcome the limitations faced by previous blockchain projects.
I. State Sharding: A Scalable Solution for Blockchain Infrastructure
A. Harmony’s implementation of sharding creates multiple groups or “shards” of validators that process transactions concurrently, achieving high throughput and low latency.
B. Unlike other sharding-based blockchains, Harmony shards the network communication, transaction validation, and blockchain state, making it fully scalable.
II. Adaptive Consensus Protocol: Ensuring Security and Energy Efficiency
- A. Harmony’s consensus algorithm, Fast Byzantine Fault Tolerance (FBFT), is linearly scalable in terms of communication complexity and improves upon the Practical Byzantine Fault Tolerance (PBFT) used by other blockchain platforms.
- B. The platform’s Proof-of-Stake (PoS) mechanism ensures an energy-efficient and secure consensus protocol.
- C. Harmony’s adaptive-thresholded PoS adjusts the threshold of stakes required for a node to join the network based on the volume of total staking, preventing malicious stakers from concentrating their power in a single shard.
III. Efficient Networking Solutions: Enhancing Cross-Shard Communication and Transaction Speeds
- A. Harmony adopts RaptorQ fountain code and Kademlia routing to enable fast block propagation within shards and across the network, ensuring that cross-shard transactions scale logarithmically with the number of shards.
- B. The platform’s Fast State Synchronization allows new nodes to join the network quickly and efficiently.
- C. Harmony supports home nodes and locator mobility for better network utilization, further enhancing the platform’s scalability and performance.
Harmony: Revolutionizing Blockchain Technology with Scalability, Security, and Energy Efficiency
Harmony is a next-generation blockchain platform that was developed to address the challenges of scalability, security, and energy efficiency that have plagued previous blockchain projects like Bitcoin and Ethereum. The platform combines the best research and engineering practices to create a fully scalable, provably secure, and energy-efficient blockchain infrastructure.
One of the key innovations of Harmony is its use of sharding, a technique that creates multiple groups or “shards” of validators and enables them to process transactions concurrently. This approach allows Harmony to achieve high throughput and low latency without sacrificing security or decentralization. Unlike other sharding-based blockchains, Harmony shards not only the network communication and transaction validation, but also shards the blockchain state, making it fully scalable.
Harmony’s sharding process is provably secure thanks to its distributed randomness generation (DRG) process, which is unpredictable, unbiaseable, verifiable, and scalable. Harmony also reshards the network in a non-interruptive manner to prevent against slowly adaptive byzantine adversaries. The platform’s consensus algorithm is based on proof-of-stake (PoS), which is energy-efficient and allows for fast finality. Harmony uses an adaptive-thresholded PoS that adjusts the threshold of stakes required for a node to join the network based on the volume of total staking, preventing malicious stakers from concentrating their power in a single shard.
Harmony: The Future of Blockchain Technology with Scalable Networking and Linearly Scalable Consensus Protocol
Harmony also features a scalable networking infrastructure that uses RaptorQ fountain code to propagate blocks quickly within shards or across the network. The platform adopts Kademlia routing to achieve cross-shard transactions that scale logarithmically with the number of shards. Harmony supports cross-shard transactions with shards directly communicating with each other, using an atomic locking mechanism to ensure the consistency of cross-shard transactions.
Harmony’s consensus protocol is a critical aspect of the blockchain infrastructure, as it determines how validators reach consensus on the next block. The platform’s consensus algorithm, called Fast Byzantine Fault Tolerance (FBFT), is linearly scalable in terms of communication complexity, making it a significant improvement over the Practical Byzantine Fault Tolerance (PBFT) used by other blockchain platforms.
FBFT Consensus Algorithm: The Robust and Secure Method Behind Harmony’s Scalable Blockchain Platform
In FBFT, the leader constructs the new block and broadcasts the block header to all validators. The validators check the validity of the block header, sign the block header with a Boneh-Lynn-Shacham (BLS) signature, and send the signature back to the leader. The leader waits for at least 2f + 1 valid signatures from validators (including the leader itself) and aggregates them into a BLS multi-signature. The validators then verify the transactions in the block content broadcasted from the leader, sign the received message, and send it back to the leader. Finally, the leader waits for at least 2f + 1 valid signatures (can be different signers from Step 3), aggregates them together into a BLS multi-signature, and creates a bitmap logging all the signers. The leader then commits the new block with all the multi-signatures and bitmaps attached, and broadcasts the new block for all validators to commit.
The validators of Harmony’s consensus are elected based on Proof-of-Stake (PoS). Therefore, the actual protocol differs slightly from the one described above, in a sense that a validator with more voting shares has more votes than others, rather than one-signature-one-vote. The platform’s PoS mechanism adjusts the threshold of stakes required for a node to join the network based on the volume of total staking. This ensures that small stakers can still participate in the network and earn rewards, while preventing malicious stakers from concentrating their power in a single shard.
Harmony’s Sharding Scheme and FBFT Consensus: A Secure and Efficient Solution for Scalable Blockchain Infrastructure
Harmony’s consensus protocol is more efficient than other sharding-based blockchains, such as PBFT, which has O(N) communication complexity, making it unscalable for blockchain systems with hundreds or thousands of nodes. FBFT’s use of BLS multi-signatures and RaptorQ fountain code speeds up the block broadcasting process and improves scalability, while also providing a secure and energy-efficient consensus protocol that can support a wide range of decentralized applications.
Harmony’s sharding scheme is a full sharding solution that uses PoS-based distributed randomness generation (DRG) to assign nodes to shards. Harmony has a beacon chain that serves as the randomness beacon and identity register, while multiple shard chains store separate blockchain states and process transactions concurrently. To generate a secure random number for sharding, Harmony uses an efficient algorithm that combines Verifiable Random Function (VRF) and Verifiable Delay Function (VDF). This protocol has O(n) complexity and is faster than the RandHound protocol used by Omniledger. The VDF delays the revelation of the final randomness, preventing a malicious leader from biasing the randomness by cherry-picking a subset of the VRF random numbers. By using PoS in the sharding process, Harmony shifts the security consideration of a shard from the minimum number of nodes to the minimum number of voting shares.
In Harmony, the consensus and sharding process is divided into fixed time intervals called epochs. At the beginning of each epoch, a random number is generated using the DRG protocol, and the sharding structure is determined based on that randomness. Validators who want to validate transactions in an epoch need to stake their tokens during the previous epoch before the randomness preimage is committed to the blockchain.
Harmony’s PoS-based Validator Registration: A Secure and Decentralized Approach for Sharding by Voting Shares
Harmony uses proof-of-stake (PoS) as the validator registration mechanism. In order to become a validator, participants have to stake a certain amount of tokens. The number of tokens staked will determine the number of voting shares assigned to the validator. Each voting share corresponds to one vote in the BFT consensus. At the beginning of each epoch, new validators’ voting shares are randomly assigned to shards, and the new validators join the shard(s) where their voting shares get assigned.
To prevent a large-stake attack, Harmony shards by voting shares instead of validators. After the randomness is revealed at the start of the current epoch, a random permutation on all the voting shares is done, and the permuted list of voting shares is divided evenly into m buckets, where m is the number of shards. The voting shares falling in the i-th bucket are assigned to shard i, and the corresponding validators become validators for that shard.
Adaptive-thresholded PoS: Ensuring Security and Decentralization of Harmony’s Shards
Harmony’s adaptive-thresholded PoS guarantees the security of a single shard by adaptively adjusting the price of a voting share and assigning individual voting shares to shards rather than individual validators. The price of a voting share is set algorithmically so that it’s small enough that malicious stakers cannot concentrate their voting power in a single shard. The probability distribution of the number of malicious voting shares in each shard can be modeled as a hypergeometric distribution. The actual failure rate of a shard follows a cumulative hypergeometric distribution CDF, which when N is large, degrades to binomial distribution. Harmony sets the security parameter λ to 600 to guarantee the high security of its shards.
Harmony is a sharding-based blockchain that aims to provide high scalability and fast transaction processing while maintaining security and decentralization. To achieve these goals, Harmony employs several key features, including a random state sharding scheme, an adaptive consensus protocol, fast state synchronization, and efficient networking. Harmony also introduces the beacon chain, which serves as the chain for stakers and strengthens the security of the shard chains. Furthermore, Harmony adopts Kademlia-based routing for cross-shard communication, erasure code for efficient broadcasting, and FEC-based unicast for faster and more reliable message transmission. Lastly, Harmony supports home nodes and locator mobility for better network utilization. With these features, Harmony has the potential to become a highly scalable and secure blockchain platform that can support a wide range of decentralized applications.