1. What is IPI and what blockchain problems does it aim to solve?

IPI (INDEPENDENT PROTOCOL INFRASTRUCTURE) is a next-generation blockchain project designed to address scalability issues that limit the widespread adoption of blockchain technology. It uses a novel two-phase ‘PROOF OF NETWORK’ consensus mechanism that separates the queuing of transactions from their execution. With this, IPI aims to achieve near unlimited transaction throughput (TPS), low transaction fees and a decentralised architecture to enable the global adoption of blockchain in various domains such as financial services, gaming and real-time applications.

2. What is IPI’s innovative consensus mechanism, ‘PROOF OF NETWORK’?

The ‘PROOF OF NETWORK’ (PoN) mechanism is a two-phase consensus approach. In the first phase, ‘Order Now’, the network determines the order in which transactions are executed in a distributed manner. This established order is then shared (sharded). As transactions are deterministic and their order is fixed, the outcome of their execution is already guaranteed. In the second phase, ‘Execute Later’, the network participants actually execute the transactions in order to know their results. Thanks to the fixed order and the deterministic nature of the execution, validators do not need to know the results of previous transactions to process subsequent blocks.

3. How does IPI achieve scalability with its sharding architecture?

IPI uses a multi-tier sharding architecture based on user addresses. The network initially operates as a single ‘Root’ blockchain. As the number of transactions and validators grows, the system splits into shards (level two), and when each shard reaches a certain limit (‘MaxShardsPerLevel’), it can further split into more shards, creating a hierarchy. Each shard is responsible for processing transactions related to a specific address range (defined by the address bit prefix). ‘Root’ blockchain coordinates and finalises the order of blocks from each shard, ensuring global consistency. Shards can also merge if their load falls below a certain threshold.

4. What does transaction processing look like in an IPI network with sharding?

When a user initiates a transaction, it is routed to the appropriate shard based on the sender’s address. The validators in this shard place the transaction in their mempool. The selected leader (proposer), using the Verifiable Random Function (VRF), proposes a block containing the transaction. The block is then verified and validated by a sufficient number of validators in the shard by voting (soft vote and certify vote). Once validated in the shard, the hash of the shard block is sent to the ‘Root’ blockchain mempool. The ‘Root’ blockchain leader includes the hashes of the blocks from the different shards in a new ‘Root’ block. Once the ‘Root’ block is validated, the transaction is considered published and finalised globally. Any participant in the network can verify the transaction and calculate account balance changes.

5. What is the role of validators in the IPI network and how are they rewarded?

Validators in the IPI network are mainly responsible for prioritising transactions in their assigned shards and in the ‘Root’ blockchain. In order to become a validator, a certain number of IPI tokens must be locked up as their stake. Validators participate in the consensus process by proposing and voting on blocks. They are rewarded for their work by sharing transaction fees and block rewards. Transaction fees are shared between validators at all levels of the shard hierarchy (some fees go to higher level validators). Block rewards are shared between the blockchain’s ‘Root’ validators and the validators in the shards (in proportion to the size of the shard’s address space), and within the shard the reward is shared between the block proposer and the other validators.

6. How does IPI ensure decentralisation and prevent transaction censorship?

IPI aims for a high degree of decentralisation through the use of address-based sharding, which keeps block sizes relatively small and processable on moderately powerful hardware (e.g. Raspberry Pi). The fact that validators are mainly concerned with transaction queuing rather than computationally intensive execution lowers the barriers to entry for potential validators. The use of the Pure Proof of Stake mechanism, in which block leaders and validation committees are randomly selected using VRF, makes transaction censoring significantly more difficult. In order to censor a transaction, validators would have to reject a block proposal, risking the loss of prizes, and a different set of validators is selected in the next round.

7. What are the main phases of IPI token distribution and when is the listing on exchanges (CEX) planned?

The distribution of IPI tokens takes place in phases, which include private sales (5 phases), public sales (10 phases) and listing on centralised exchanges (CEX). The price of the IPI token increases during the successive sales phases. After the public pre-sale phase, IPI will be listed on CEX exchanges. This phase is crucial as it will enable independent developers to create decentralised applications (dApps) on the IPI platform. Demand for the IPI token is expected to increase as it will be necessary for the dApps to operate and pay transaction fees.