What is Delayed Proof of Work?
Delayed Proof of Work (dPoW) is a type of security mechanism that was created by Komodo project. It is a modified version of Proof-of-Work (PoW). dPoW uses the hashpower of Bitcoin network to increase the network security.
Komodo developers are able to secure the native network but also extend the security feature to the third-party chain that is working in tandem with the Komodo ecosystem. This type of model is applicable on any blockchain network that uses the UTXO infrastructure.
How does Delayed Proof of Work Function?
The dPoW security mechanism was created and implemented by Zcash code base. In this manner, it has zero-knowledge privacy and added network security to leverage Bitcoin hash rate. The Komodo network takes a screen shot of native blockchain after every 10 minutes.
This screenshot is added to the block during a process called notarization. In this manner, Komodo network consists of backup for the entire Komodo system that is saved on the Bitcoin network.
The community-elected notary nodes on Komodo inscribe a block hash from each dPoW-protected blockchain on its distributed ledger. The recording takes place when a transaction is processed on the Komodo blockchain. The notary nodes can store a single block hash on the Komodo nework using the OP_Return command.
The ten-minute delay is to grant time for block validity. During this delay all nodes on the blockchain reach a consensus for each block. Meanwhile, the notary nodes record block hash from a previously-mined block.
In the next stage, notary nodes write block hash from Komodo to Bitcoin ledger. This process is completed during a Bitcoin transaction and running OP_Return to write the data into a Bitcoin block. Following the notarization of Bitcoin, Komodo notary nodes inscribe the data from Bitcoin chain to other protected chains.
At this point, the notarized blocks become immutable. dPoW is used with Bitcoin but it has security and other features that are compatible with other blockchain networks that are using the UTXO model.
Differences and Similarities Between PoW and dPoW
PoW model ensures network security and prevent threats such as distributed denial-of-service attacks (DDoS). At the same time, PoW is expensive but easier for verification and an important part of the mining process.
Mining using PoW blockchain is an intrinsically demanding process that requires a lot of efforts. Miners have to commit intense computational work and solve complex encryption puzzles to mine a new block.
Therefore, miners operating on a PoW blockchain need to generate a lot of computation power using expensive hardware and software upgrades. Furthermore, miners also need to account for power supply charges such as electricity expenses etc.
Nevertheless, mining is an important process that secures the network against external attacks and verifies the authenticity of recorded transactions to generate new tokens to incentivize the miners.
On the other hand, dPoW are not used to reach a consensus for the transaction records. Instead, it is implemented as an additional layer of PoW mechanism. With dPoW, the notarized blocks cannot be reorganized to make it more resistant against 51% attacks. dPow resets the rules of consensus for each turn of block notarization.
Most PoW blockchains use longest chain rule therefore when a blockchain receives a notification about a new block notarization, the longest chain starts from a new position and will not validate the longest chain on the previous location.
Advantages of Delayed Proof of Work (dPoW)
Here are some important advantages that are associated with dPoW mentioned as under:
- It adds an additional layer of security for PoW blockchains and increases the block integrity.
- dPoW prevents 51% attack affecting a PoW blockchain network.
- dPoW changes the rules of consensus for every time a block is notarized to secure it against security threats.
- dPoW security measure is compatible with any blockchain that is based on UTXO.
The delayed Proof of Work security creates a backup of a PoW blockchain that protects the blockchain against system failure and hack attacks. This system ensures that blockchain data can be recovered and the attackers have to take down the Bitcoin blockchain to destroy the snapshots that are hacked on the network during the block notarization process.