What is Solana’s Proof of History?

Yakovenko and the Solana team found a way to utilize that method in a blockchain-based system by using a similar mechanism to the nLocktime feature that can be found in the original blockchain protocol – Bitcoin. NLocktime allows for postdate transactions using block height instead of timestamps. As it turns out, this is a cryptographically-secure way to show that time has passed.

The same principle is used to power Solana’s key innovation – the novel Proof of History algorithm. However, the Solana team has refined the approach by using a much more granular verifiable delay function, a SHA 256 hash chain, which is used to checkpoint the Solana ledger and coordinate consensus. Essentially, this method assigns a cryptographic clock to every transaction. 

According to Solana, thanks to this method, the protocol could theoretically reach 710,000 transactions per second, or the theoretical limit of a 1GB centralized network.