$SOL
Blockchain is an implementation of a fault tolerant replicated state machine.
Current publicly available blockchains do not rely on time, or make a weak
assumption about the participants abilities to keep time
Each node in the network usually relies on their own local clock without knowledge of any
other participants clocks in the network. The lack of a trusted source of time
means that when a message timestamp is used to accept or reject a message,
there is no guarantee that every other participant in the network will make
the exact same choice. The PoH presented here is designed to create a ledger
with verifiable passage of time, i.e. duration between events and message
ordering. It is anticipated that every node in the network will be able to rely
on the recorded passage of time in the ledger without trust.
2 Outline
The remainder of this article is organized as follows. Overall system design is
described in Section 3. In depth description of Proof of History is described
in Section 4. In depth description of the proposed Proof of Stake consensus
algorithm is described in Section 5. In depth description of the proposed
fast Proof of Replication is described in Section 6. System Architecture and
performance limits are analyzed in Section 7. A high performance GPU
friendly smart contracts engine is described in Section 7.5
3 Network Design
As shown in Figure 1, at any given time a system node is designated as
Leader to generate a Proof of History sequence, providing the network global
read consistency and a verifiable passage of time. The Leader sequences user
messages and orders them such that they can be efficiently processed by other
nodes in the system, maximizing throughput. It executes the transactions
on the current state that is stored in RAM and publishes the transactions
and a signature of the final state to the replications nodes called Verifiers.
Verifiers execute the same transactions on their copies of the state, and pub-
lish their computed signatures of the state as confirmations.#solana